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Management Recommendations
for
Candystick or Sugarstick (Allotropa virgata Torrey & Gray)

v. 2.0

by

N. S. Wogen and J. D. Lippert

December 1998


TABLE OF CONTENTS

EXECUTIVE SUMMARY 1
I. NATURAL HISTORY 4
A. Taxonomic/Nomenclatural History 4
B. Species Description 4
1. Morphology 4
2. Reproductive Biology 5
3. Ecology 6
C. Range, Known Sites 7
D. Habitat Characteristics and Species Abundance 8
II. CURRENT SPECIES SITUATION 9
A. Why Species is Listed under Survey and Manage Standards and Guidelines 9
B. Major Habitat and Viability Considerations 9
C. Threats to the Species 9
D. Distribution Relative to Land Allocations 10
III. MANAGEMENT GOALS AND OBJECTIVES 11
A. Management Goals for the Taxon 11
B. Specific Objectives 11
IV. HABITAT MANAGEMENT 11
A. Lessons from History 11
B. Identification of Habitat Areas for Management 11
C. Management Within Habitat Areas 12
D. Other Management Issues and Considerations 13
V. RESEARCH, INVENTORY, AND MONITORING NEEDS 13
A. Data Gaps and Information Needs 13
B. Research Questions 13
C. Monitoring Needs and Recommendations 14
VI. REFERENCES 15

EXECUTIVE SUMMARY

Species: Allotropa virgata Torrey & Gray (Candystick or Sugarstick)

Taxonomic Group: Vascular Plants

ROD Components: 1, 2

Other Management Status: In Oregon, Washington, and California Allotropa virgata has not been placed on any agency sensitive plant lists.

Range: Allotropa virgata is found in deep humus of coniferous forests at lower elevations, east slope of the Cascades to near the coast, from British Columbia to California. Noteworthy disjunctions occur in Idaho and Montana (USDA, Forest Service, and USDI, Bureau of Land Management 1994a). It is widespread, but formerly perceived as rare throughout the range. Within the range of the northern spotted owl the species occurs on several National Forests and BLM Districts.

Specific Habitat: Allotropa virgata occurs in closed canopy pole (Oregon coastal strand), mature, and old-growth seral stages in Pseudotsuga menziesii (Douglas-fir), Tsuga heterophylla (western hemlock), Abies grandis (grand fir), Abies amabilis (silver fir), Pinus contorta (lodgepole pine), Lithocarpos densflorus (tanoak) and Abies magnifica (red fir) vegetation series, ranging from sea level along the Oregon coast to 3048.78 m (10,000 feet) at inland sites. It is not restricted to old-growth, but the largest populations occur there. It has been observed in 60 year old stands at inland sites with 4.33 cm (11 inches) diameter trees, but does not appear to tolerate competition in those conditions. It occupies dry, well-drained soils, with abundant coarse woody debris (especially decay classes 4 and 5) within most of the range. It appears substrate specific to decaying wood, with individuals at an Idaho site restricted to the buried margin of a partially decomposed log. (USDA, Forest Service, and USDI, Bureau of Land Management 1994a). Allotropa virgata is a nongreen mycotrophic species requiring an association with a fungus and a green vascular plant. Moisture is thought to be critical for the mycorrhizal component which is associated with Allotropa virgata. Decaying wood is thought to provide important moisture and nutrient reserves (Dimling 1997a).

Within the Oregon coastal strand, a 4.83 km (3 mile) strip of land immediately adjacent to the Pacific Ocean, the species occurs at elevations of 3.05-91.46 m (10-300 feet) and is found in 35-85 year old Pinus contorta (lodgepole pine) forests. Abundant summer fog in these areas seems to alleviate the need for coarse woody debris, which is found in drier conditions (Dimling 1997a). Within the California coast range and Klamath Mountains, Allotropa is associated with early mature Lithocarpus densiflorus (tanoak) series and Pseudotsuga menziesii/Lithocarpus (Douglas fir/tanoak) plant associations. On the east side of the Cascades in California, Allotropa is associated with Abies magnifica/Pinus contorta (red fir/lodgepole pine) plant associations at elevations above 5000 feet.

Threats:

  • Fragmentation of suitable habitat causing reduction of effective population size and subsequent loss of important genes
  • Forest management activities such as thinnings, shorter rotations, regeneration harvest, road building, and mechanical disturbance to duff and soil layers
  • Reductions in coarse woody debris inputs into Allotropa virgata habitat below Northwest Forest Plan levels
  • Disturbance of duff or soil layers from activities such as unauthorized raking and digging associated with commercial and recreational matsutake mushroom harvest and other activities that cause soil compaction
  • Trampling and plant collection from recreational activities, such as hiking and horseback riding along trails where Allotropa virgata occurs
  • Livestock grazing is occurring within Allotropa virgata populations and has been observed to cause the removal of reproductive stems from plants (Lisa Wolf, personal communication 1995)
  • Browsing by deer and other mammals has been reported, which may reduce reproductive potential (Dimling 1997a)
  • Noxious and exotic weeds in and around Allotropa virgata habitat

MANAGEMENT RECOMMENDATIONS

Populations along the Oregon coastal strand within 4.83 km (3 miles) from the ocean (Siuslaw NF), in the California Coast Range (Six Rivers NF) and populations in the central core of the range in the Cascades and Klamath Mountains (Gifford Pinchot NF, Washington south through Klamath and Modoc NFs, California) will not receive any special management under this plan (see page 11 for rationale).

Populations on the fringe of the range [Willamette and Umpqua Valley (Salem, Roseburg, Eugene Districts BLM); east side Cascades in Washington (Wenatchee and Okanagan NF); Oregon Coast Range Province not including the coastal strand (Coos Bay, Eugene, Salem Districts BLM, and Siuslaw NF); west side North Cascades (Olympic and Mt. Baker-Snoqualmie NFs); and California south of Klamath NF (Shasta-Trinity, Lassen and Mendocino NFs) will be protected and subject to these management recommendations.

  1. Maintain potential host trees (conifer species) using Green Tree Retention clumps or other retention areas to buffer populations from management activities in order to maintain mycorrhizal connection. Green Tree Retention guidelines will be consistent with Standards and Guidelines set forth in USDA, Forest Service, and USDI, Bureau of Land Management, Record of Decision (1994b).
  2. Retain at least 70 percent cover of host and nonhost trees (conifer and hardwoods) within retention areas to provide a continuous supply of coarse woody debris and to maintain quality of the duff layer and mycorrhizal connections over time.
  3. Maintain or enhance coarse woody debris within the vicinity of populations by protecting existing coarse woody debris as well as enhancing coarse woody debris by implementing 2 above, which will provide for new recruitment material into Allotropa virgata sites. Coarse woody debris guidelines will be consistent with Standards and Guidelines set forth in USDA, Forest Service, and USDI, Bureau of Land Management (1994b).
  4. Avoid duff and soil disturbance, including soil compaction, within the vicinity of populations where damage to mycorrhizal connections could occur from mechanical equipment and other ground-disturbing activities.
  5. Avoid hot burns where duff and litter are consumed within the vicinity of populations. Use of prescribed burning, where burns can be maintained as low intensity cool burns, is acceptable if populations are monitored pre- and post-burn to determine effects of this management action. Use the concept of adaptive management to guide further prescriptions.
  6. In areas where matsutake harvest occurs, prevent raking in order to maintain mycorrhizal networks.
  7. During reauthorization of grazing permits, Allotropa virgata sites should be evaluated to determine if there are impacts. If plants are being directly affected, grazing permits could be modified by using seasonal restrictions or by implementing exclosures.
  8. For recreational impacts such as picking, trampling, Off Highway Vehicle use (OHV), and trail development, assess impacts and, where necessary, prescribe mitigation measures such as closing or rerouting trails or OHV closures.
  9. Control noxious or exotic weed populations that compete with Allotropa virgata.

Information Needs

  • Monitor Allotropa virgata within managed areas to determine effectiveness of these management recommendations.
  • Determine effects of prescribed burning and matsutake harvest on Allotropa virgata.

I. NATURAL HISTORY

A. Taxonomic/Nomenclatural History

Scientific name: Allotropa virgata T. & G. ex Gray

Common name: candystick, sugarstick

Family: Ericaceae (Heath family)

Subfamily: Monotropoideae

Genus: Allotropa virgata is a monotypic genus (contains only a single species).

Species: Allotropa virgata was first collected by the Wilkes expedition in the Cascade Range of Washington in the late 1800s (Hitchcock et al. 1959).

Citation: T. & G. ex Gray, Proc. Am. Acad. 7:368. 1867

Synonyms: None

B. Species Description - T. & G. Ex Gray 1867; Hitchcock 1959; Abrams 1951; Peck 1961; Munz 1959; Jepson 1993.

1. Morphology

The following species description is from Lichthardt and Mancuso (1991):

Allotropa virgata is sometimes termed a "monotrope" referring to the species affiliation with the Monotropoideae, a subfamily of plants within the Ericaceae that lack chlorophyll.

Nontechnical description: Fleshy, nongreen plants with single or more often clustered, unbranched stems bearing the flowers and small, pointed leaves. The thick, brownish-red stems stand up to 40 cm (15.75 inches) tall. Stems are striped vertically with red and white, this feature being most obvious toward the base of the stem (small stems may be solid red). Flowers are similar in color to the stem and round in outline. An important feature of the flowers is that they open outward, directly away from the stem, as opposed to turning down as in closely related species (see below). Standing dead stems from previous years are almost always present. Old stems are dark reddish-brown with no white, and hollow.

Technical description: Achlorophyllous, simple-stemmed herbs with single to numerous stems, originating from a diffuse, root system bearing branch roots and adventitious buds at intervals along its length; stems 1-4 dm (3.94-15.75 inches) tall, white and pink (red) striped, 5-10 mm (.19-.39 inches) thick, enlarged below-ground; leaves reduced, scale-like, pinkish to yellow-brown, linear lanceolate; inflorescence a terminal, elongate, spikelike raceme, 5-20 cm (1.97-7.87 inches) long; flowers axillary and exceeded by the subtending bract, often with 1-2 bracteoles below the calyx; sepals 5, distinct, white or pinkish to brownish, about 5 mm (.20 inches) long; corolla lacking; stamens 10, purplish, opening by basal (falsely terminal) pores, from about equal, to twice as long as, the sepals; pistol 5-capillary, styles very short, stigma shallowly 5-lobed; ovary superior, 5-celled, with axile placentation; fruit a capsule.

Similar species: Allotropa virgata may be confused with other nongreen members of the Heath family, which often share the same habitat. Pterospora andromedea (pinedrops) has sticky, brown flowering stems that also dry and persist a long time after dying. Unlike Allotropa virgata, its flowers face downward, borne at the ends of delicate, reflexed pedicels. It is generally much taller than Allotropa virgata (3 dm [11.81 inches] to over 1 meter [39.37 inches]). Hypopitys monotropa (pinesap) is similar in height to Allotropa virgata, but is uniformly pinkish to straw-colored, drying to black. In flower, the main stem bends over (nods) distinctly, but straightens again as fruits develop.

Some nongreen orchids, especially Corallorhiza spp.(coralroot), are sometimes mistaken for Allotropa virgata. Coralroot has slender stems, rather variable in color from purplish to reddish-brown to albino. However, stems do not bear the small, pointed leaf blades always present on Allotropa virgata.

Figure 1. Allotropa virgata (line drawing)

Figure 1. Allotropa virgata (Hitchcock et al. 1959)
Reprinted by permission of the University of Washington Press

2. Reproductive Biology

Lichthardt and Mancuso (1991) describe the reproductive biology of Allotropa virgata as a clonal species that spreads by rhizomes, bearing adventitious buds on an extensive root system. When buds develop into a new root crown the connection with the old one is severed. Each new "plant" propagated in this way is genetically identical to the one before and is referred to as a ramet to distinguish it from an individual propagated by seed or genet. Each successive ramet apparently maintains ties to an established network of fully colonized mycorrhizal roots until such time that flowering can occur. Successive ramets may be as far as 1 m (39.37 in.) apart. In one case where there was a linear pattern of old stems, excavation revealed that the growth of the plant followed a buried log.

Because the species can spread vegetatively, there is some question as to how many genets actually occur in a population. This can lead to an overestimation on the number of distinct individuals occurring in a population (Dimling 1997a).

Allotropa virgata is pollinated by bumblebees (Bombus), which are rewarded by big nectar pools that accumulate at the base of the ovary. Flowers may be autogamous because seed set is abundant, even when plants were covered by screens to keep pollinators out. Seeds of Allotropa virgata are minute and linear, about 1 mm (.04 in.) long and probably composed of less than 20 cells. Seeds are abundant, more than 100 per capsule, and wind-dispersed. Because of their small size they drift very slowly to the ground, kept aloft by air currents. The small seeds lack nutrient reserves and must establish a mycorrhizal association immediately upon germinating - possibly even before. All attempts at germinating seeds in the lab, in the presence of a suitable fungus, have failed (Lichthardt and Mancuso 1991).

Allotropa virgata may not flower or emerge above ground every year, as documented for several close relatives. Although not known for Allotropa virgata, some individuals of achlorophyllous ericads may be dormant for as many as 13 years between flowering episodes. Dead stems are thought to be visible for several years after flowering. Climatic conditions are also thought to play a role in the presence, absence, and abundance of stems visible in a given year with moisture being a possible limiting factor. Limited data on flowering frequency is available. It has been reported a perennial species. (USDA, Forest Service, and USDI, Bureau of Land Management 1994a; Lichthardt 1995).

3. Ecology

Although often referred to as a saprophyte, Allotropa virgata, like its nongreen relatives, is actually a mycotroph. Mycotrophic plants obtain necessary nutrients and carbon compounds from a fungus associated with its roots. For Allotropa virgata, the mycorrhizal fungi are commonly associated with roots of conifers such as Douglas-fir (Pseudotsuga menziesii) and lodgepole pine (Pinus contorta). In portions of the species' range some hardwood species may also serve as host trees (Lichthardt and Mancuso 1991). Rhizopogon vinicolor (Castellano and Trappe 1985), Cenococcum geophilum and Tricholoma magnivelare (matsutake) (Lichthardt 1995) have been observed to occupy roots of Allotropa virgata.

Because of its dependent nature, the habitat in which Allotropa virgata is found may primarily be a function of the requirements of the fungus, with important factors being those of the soil environment and the availability of host trees. Buried, rotten wood is one important aspect of Allotropa virgata habitat, probably because it retains moisture and provides mineral or organic substances essential to the associated fungus (Lichthardt and Mancuso 1991), especially during the dry season.

The dependence of mycotrophic plants on conifer photosynthates suggests that anything that destroys the tree component or severs the mycorrhizal relationship will result in death of the mycotroph (Lichthardt and Mancuso 1991). The Gifford Pinchot National Forest documented the persistence of Allotropa virgata in a timber harvest unit where 70 percent conifer basal area was maintained, suggesting that some or all of the host trees were left undisturbed. Basal area retention of 5 percent on a site in the Umpqua National Forest eliminated Allotropa virgata. Opening up the canopy may also create competition among mycorrhizal mycelia. Competing vascular plant species that are likely to establish in areas where canopy cover has been altered may have completely different mycorrhizal associates causing a shift in vascular plant composition. A shift in the mycorrhizal community may have deleterious effects on Allotropa virgata (Dimling 1997a).

In Idaho, Lichthardt and Mancusco (1991) reported that Allotropa could survive ground fires that do not affect overstory host trees. Such ground fires are generally cool burns in which the underground root system may not be adversely impacted (Dimling 1997a).

It is still not clear what role mammals play in the dispersal of Allotropa virgata. It has been suggested that small mammals and ungulates such as deer may be important in seed dispersal. Deer have been observed to routinely browse plants. It has been suggested that browsing may affect the reproductive capacity of plants (Dimling 1997a). Deer compact and disturb duff and soil layers less than other grazing animals.

C. Range, Known Sites

Allotropa virgata occurs in deep humus of coniferous forests at lower elevations, east slope of the Cascades to near the coast, from British Columbia to California. Noteworthy disjunctions occur in Idaho and Montana (USDA, Forest Service, and USDI, Bureau of Land Management 1994a). The species is widespread and formerly perceived as rare throughout the range. Dimling (1997) reported that out of 716 occurrences of Allotropa virgata, 30 were located in California, 74 were located in Washington, and 612 occurred in Oregon. The majority of sites from Oregon were found at higher elevations in the Cascades. Within the range of the northern spotted owl, the species occurs on several National Forests and BLM Districts in California, Washington, and Oregon. Since the spring of 1997, hundreds of additional sites have been located within the Cascades and Klamath Mountains, between the Gifford Pinchot National Forest and the Klamath National Forest.

D. Habitat Characteristics and Species Abundance

Allotropa virgata occurs in closed canopy pole (Oregon coastal strand), mature, and old-growth seral stages in Pseudotsuga menziesii (Douglas-fir), Tsuga heterophylla (western hemlock), Abies grandis (grand fir), Abies amabilis (silver fir), Pinus contorta (lodgepole pine), Lithocarpus densiflorus (tanoak) and Abies magnifica (red fir) vegetation series, ranging from sea level along the Oregon coast to 3048.78 m (10,000 feet) at inland sites. It is not restricted to old-growth, but the largest populations occur there. It has been observed in 60 year old stands at inland sites with 11 cm (4.33 inches) diameter trees, but does not appear to tolerate competition in those conditions. U. S. Forest Service ecology program ecoplot data indicates that Allotropa virgata occurs in a wide range of plant associations and is often found in low densities within ecoplots. Most sites have less than ten stems; however, some populations have over 100 stems. Populations, although widespread, are often highly isolated. Allotropa often occupies dry, well-drained, acidic soils, with abundant coarse woody debris (especially decay classes 4 and 5), and appears substrate specific to decaying wood or well-developed duff layer, with individuals at an Idaho site restricted to the buried margin of a partially decomposed log (USDA, Forest Service, and USDI, Bureau of Land Management 1994a).

Observations suggest that coarse woody debris is a critical habitat component for this species, providing moisture and nutrient reservoirs, especially during droughty summer months except within the Oregon coastal strand where abundant summer fog provides needed moisture (Dimling 1997b). In these stabilized coastal dunes, Allotropa virgata is strongly associated with 35 to 85 year old Pinus contorta (lodgepole pine) forests which occur at elevations of 10-300 feet. Within the Oregon coastal strand, habitats that support and maintain populations of Allotropa lack late-successional and old-growth characteristics.

In the California coast range and Klamath Mountains, Allotropa is closely associated with the tanoak series. Populations are found in early to mid-mature forests. Stands in the Coast Range exhibit evidence of fire history; most have remnant wolf trees.

Allotropa in the California Cascades is most abundant on the east side of the mountains. It is associated with Abies magnifica/Pinus contorta (red fir/lodgepole pine) associations at elevations above 5000 feet. In this part of the range, Allotropa is not associated with a deep duff layer. Allotropa virgata is an achlorophyllous (nongreen) species, requiring an association with a mycorrhizal associate (fungus) that in turn is dependent on a green vascular host.  Within the range of the northern spotted owl, the primary photosynthetic hosts appear to be conifers, primarily Pseudotsuga menziesii (Douglas-fir) and Pinus contorta (lodgepole pine), but hardwood tree species are probable hosts as well. Competition between mycorrhizal mycelia from other vascular plant species may be a limiting factor in some Allotropa virgata habitat conditions. Evidence suggests that it is necessary to maintain approximately 70 percent canopy closure to maintain mycorrhizal hosts and to reduce shifts in underground mycorrhizal species (Dimling 1997b). Shifts in underground mycorrhizal species often lead to changes in the above ground plant communities (Dimling 1997b).

II. CURRENT SPECIES SITUATION

A. Why Species is Listed under Survey and Manage Standards and Guidelines

The cumulative effects assessment suggests that this species may be restricted in large part to federal lands in the future. This would result in large gaps in the species historic range, particularly in northern California, northern Oregon, and southwestern Washington coast range provinces. In addition, riparian protection afforded by buffers and key watersheds may increase pressure to log upland sites, placing rare dry site species at greater risk (USDA, Forest Service, and USDI, Bureau of Land Management 1994a).

B. Major Habitat and Viability Considerations

Given the great number of known sites within the range of the northern spotted owl, the viability of Allotropa virgata is expected to be secure in the core part of its range (the Cascades and Klamath Mountains from Gifford Pinchot NF in Washington south through Oregon to Klamath and Modoc NFs in California), in the Oregon coastal strand (within 3 miles of the ocean on Siuslaw NF) and within the California coast range. The surprisingly large number of sites located during the 1997 and 1998 field seasons indicate that Allotropa virgata is much more common than previously expected. Because so many sites have been located, it is assumed that non-harvest land allocations will provide for long term viability within the core area. Non-harvest allocations account for greater than 50 per cent of the land base on most National Forests and BLM Districts. Viability is not a concern for these Allotropa populations given the protection afforded them by the Record of Decision standards and guidelines and land allocations.

However, in areas on the edge of this species range (Willamette and Umpqua Valley, eastside Cascades in Washington, Oregon Coast Range Province, westside north Cascades; and California south of Klamath/Modoc NFs), viability is still a concern.

Activities that directly or indirectly affect the species and its associated habitat outside the core area include: (1) Reduction of coarse woody debris below Northwest Forest Plan levels will impact current and future habitat; (2) Actions that disturb mycorrhizal networks; (3) Actions that accelerate decomposition of the duff layer and (4) Actions that reduce reproductive potential.

C. Threats to the Species

  1. Fragmentation of suitable habitat resulting in small population sizes may affect this species ability to retain the genetic variation needed for long-term viability. Many populations are small and widely scattered and it is not known if gene migration occurs among populations.
  2. Forest management activities, including repeated thinnings, rotations shorter than 80 years, regeneration harvest, and road building activities, directly impact plants and reduce suitable habitat for species survival. During forest management activities, loss of host trees that are necessary for mycorrhizal connections, will result in loss of populations. Mechanical disturbance to duff and soil layers can also occur, potentially impacting the fungal community and mycorrhizal associates (Lichthardt and Mancuso 1991).
  3. Reductions in coarse woody debris recruitment into Allotropa virgata habitat, through actions such as salvage logging, may be reducing future suitable habitat for this species. Wildfire and other forest processes such as disease and windthrow pockets have been altered through management. These processes are important sources for coarse wood input into the system.
  4. Disturbance of soil and duff layers can affect Allotropa. Commercial and recreational matsutake mushroom harvest occurs within Allotropa virgata habitat. Raking activities can impact the fragile mycorrhizal connections necessary for plant survival by altering or removing duff layers. Excessive foot traffic within populations may also be disturbing important duff layers and mycorrhizal networks.
  5. Trampling and plant collection caused by recreational activities, such as hiking and horseback riding along trails where Allotropa virgata occurs, may be affecting individual populations, causing the loss of reproductive potential in localized sites.
  6. Livestock grazing is occurring within Allotropa virgata populations and has been observed to cause the removal of reproductive stems from plants (Lisa Wolf, personal communication 1995). Soil compaction and trampling by livestock may also disturb mycorrhizal connections.
  7. Browsing by deer and other mammals has been documented. Because of the potential to remove reproductive stems, browsing may cause declines in reproductive capacity. Allotropa virgata may have, however, evolved tanniniferous compounds to discourage ungulate browsing (Wallace 1977).
  8. Noxious and exotic weeds can compete for resources in and around Allotropa virgata habitat, reducing species vigor, reproductive potential, and suitable habitat.

D. Distribution Relative to Land Allocations

Allotropa virgata occurs within all land allocations. A recent analysis (Dimling 1997b) of approximately 700 sites from Washington, Oregon, and California indicated that 60 percent of known sites occur within Matrix and Adaptive Management Areas and 40 percent of known sites were located in Congressionally Withdrawn Areas, Administratively Withdrawn Areas, and Late-Successional Reserve Areas.

III. MANAGEMENT GOALS AND OBJECTIVES

A. Management Goals for the Taxon

The management goal Allotropa virgata is to assist in maintaining species viability within the range of the northern spotted owl.

B. Specific Objectives

Reduce habitat and population fragmentation by protecting Allotropa virgata in designated areas. Maintain suitable levels of coarse woody debris, undisturbed duff and soil layers to protect mycorrhizal networks and host trees necessary for mycorrhizal connections.

IV. HABITAT MANAGEMENT

A. Lessons from History

  1. Allotropa virgata died in stands where 95 percent of the trees have been removed and has been maintained in stands where 30 percent of the trees have been removed (Dimling, 1997a)
  2. The species has been observed to "retreat" from edges where host trees and duff layers have been removed by fire and regeneration harvest (Lichthardt and Mancuso 1991; Lichthardt 1995).
  3. Evidence of historical fire events (charcoal in soil profiles, fire scars) have been found at several Allotropa virgata sites, suggesting forest processes (not limited to fire) may have historically provided the coarse woody debris for Allotropa virgata and the fungal associate to colonize.

B. Identification of Habitat Areas for Management

Population distribution and abundance were the principle considerations in determining which geographic areas should receive management. In some portions of the species' range, few populations occur, while in other portions, many additional sites for Allotropa virgata have been recorded. Sites selected for management include: Willamette and Umpqua Valley (Salem, Roseburg, Eugene Districts BLM); East side Cascades in Washington (Wenatchee and Okanagan NF); Oregon Coast Range Province not including the coastal strand (Coos Bay, Eugene, Salem Districts BLM, and Siuslaw NF); west side North Cascades (Olympic and Mt. Baker-Snoqualmie NFs); and California south of Klamath/Modoc NFs (Shasta-Trinity, Lassen and Mendocino NFs).

C. Management Within Habitat Areas

  1. Maintain potential host trees (conifers) using Green Tree Retention clumps or other retention areas to protect populations from management activities in order to maintain mycorrhizal connection. Green Tree Retention guidelines will be consistent with Standards and Guidelines set forth in USDA, Forest Service, and USDI, Bureau of Land Management (1994b).
  2. Retain at least 70 percent cover of host and non-host trees (conifer and hardwoods) within retention areas to provide a continuous supply of coarse woody debris and to maintain the quality of the duff layer and mycorrhizal connections over time.
  3. Maintain or enhance coarse woody debris within the vicinity of populations by protecting existing coarse woody debris as well as enhancing coarse woody debris by implementing 2 above that will provide for new recruitment material into Allotropa virgata sites. Coarse woody debris guidelines will be consistent with Standards and Guidelines set forth in USDA, Forest Service, and USDI, Bureau of Land Management, Record of Decision (1994b).
  4. Avoid duff and soil disturbance, including soil compaction, within the vicinity of populations where damage to mycorrhizal connections could occur from mechanical equipment and other ground-disturbing activities.
  5. Avoid hot burns where duff and litter are consumed within the vicinity of populations. Use of prescribed burning, where burns can be maintained as low intensity cool burns, is acceptable if populations are monitored pre- and post-burn to determine effects of this management action. Use the concept of adaptive management to guide further prescriptions.
  6. In areas where matsutake harvest occurs, prevent raking in order to maintain mycorrhizal networks.
  7. During reauthorization of grazing permits, Allotropa virgata sites should be evaluated to determine if there are impacts. If plants are being directly impacted, grazing permits could be modified by using seasonal restrictions or by implementing exclosures.
  8. For recreational impacts such as picking, trampling, Off Highway Vehicles (OHV), and trail development, assess impacts and, where necessary, prescribe mitigation measures such as closing or rerouting trials or OHV closures.
  9. Control noxious or exotic weed populations that compete with Allotropa virgata.

D. Other Management Issues and Considerations

Initiate population viability analysis as more populations are located; determine the species response to management activities; and conduct inventories to determine if this species should be dropped from the Component 2 Survey and Manage strategy and guideline.

V. RESEARCH, INVENTORY, AND MONITORING NEEDS

The objective of this section is to identify opportunities for additional information which could contribute to more effective species management. The content of this section has not been prioritized or reviewed as to how important the particular items are for species management. While the inventory, research, and monitoring identified below are not required, these recommendations should be addressed by a regional coordinating body at the Northwest Forest Plan level.

A. Data Gaps and Information Needs

  1. Conduct genetic (electrophoretic) study to estimate level of genetic variation within and among populations in order to determine the contribution of peripheral populations to maintaining viability of the species.
  2. Determine the abundance and distribution of populations relative to land allocations outside the core area of Allotropa virgata, to evaluate if the species is viable in these locations.

B. Research Questions

  1. How many populations are needed to assure species viability? What is the optimum distribution and number of sites needed to maintain adequate gene exchange? Determine what constitutes a viable population. Determine genetic variation within and between populations.
  2. Determine pollinator availability, seed germination, dissemination requirements, and other life history needs of Allotropa virgata. Determine dissemination requirements of fungal host. Determine which fungal hosts are needed for Allotropa virgata to survive and establish. What is the distance(s) from Allotropa virgata to host tree(s). What species of host trees are most important in which portions of the species range? Do root exudates from tree hosts stimulate germination of Allotropa virgata seeds? Determine the requirements for the fungal host. What soil environment is needed to support the fungal mycobiont?
  3. What is the optimum patch size necessary to maintain this species and its mycorrhizal fungal host, and which stand characteristics are conducive to species establishment and maintenance?
  4. Do extant populations of Allotropa virgata and the fungal associate serve as "inoculum" for adjacent developing stands? What mechanisms are involved in successful establishment?
  5. Determine how Allotropa virgata, the mycobiont, and tree hosts establish and persist in the environment. How and when do the seeds need to encounter the mycorrhizal associate?
  6. Determine the role of ungulates and other mammals, including livestock, in the ecology of this species.
  7. Identify the factors that trigger flowering and flowering periodicity. How long does the genet remain vegetative below ground?
  8. How does timber harvest, including various stand rotation lengths, around and between Allotropa virgata sites benefit or impact this species?
  9. How long does Allotropa virgata live, and what are normal demographic patterns for the species?
  10. Is commercial or recreational matsutake harvest impacting Allotropa virgata populations?
  11. Are recreational activities impacting the viability of Allotropa virgata populations? How deep are the Allotropa virgata rhizomes?
  12. What type of management activities benefit this species? Determine the role of fire and other disturbance factors in maintaining this species through time.

C. Monitoring Needs and Recommendations

Monitoring of management activities is highly recommended to determine whether retention areas are protecting populations of Allotropa virgata from ground-disturbing activities such as timber harvest or road construction.

Monitoring should also be conducted to determine the effects of prescribed burning and matsutake harvest on Allotropa virgata.

VI. REFERENCES

Castellano, M. A. and J. M. Trappe. 1985. Mycorrhizal associations of five species of Monotropoideae in Oregon. Mycologia 77: 499-502.

Dimling, J. 1997a. Allotropa virgata Meeting Notes, Umpqua National Forest. Unpublished Meeting Notes.

Dimling, J. 1997b. Allotropa virgata Habitat and Viability Analysis. Unpublished Meeting Notes.

Hitchcock, C. L., A. Cronquist, M. Ownbey and J. W. Thompson. 1959. Vascular Plants of the Pacific Northwest. Part 4: Ericaceae Through Campanulaceae. University of Washington Press, Seattle.

Lichthardt, J. 1995. Draft Conservation Strategy For Allotropa virgata (Candystick). U.S. Forest Service Northern Region. Idaho Department of Fish and Game.

Lichthardt, J. and M. Mancuso. 1991. Report on the Conservation Status of Allotropa virgata (Candystick) on the Nez Perce National Forest I. Field Survey and First and Second-Year Monitoring Results. Idaho Department of Fish and Game. 16 pp.

Wallace, G. D. 1975. Studies of the Monotropoideae (Ericaceae): taxonomy and distribution. The Wasman Journal of Biology 33(1): 1-21.

Wallace, G. D. 1977. Studies of the Monotropoideae (Ericaceae): Floral nectaries: anatomy and function in population ecology. American Journal of Botany 64:199-206.

USDA, Forest Service, and USDI, Bureau of Land Management. 1994a. Final Supplemental Environmental Impact Statement on Management of Habitat for Late-Successional and Old-Growth Forest Related Species Within the Range of the Northern Spotted Owl. Portland OR. Appendix J2, Results of Additional Species Analysis, Portland, OR.

USDA, Forest Service, and USDI, Bureau of Land Management. 1994b. Final Supplemental Environmental Impact Statement on Management of Habitat for Late-Successional and Old-Growth Forest Related Species Within the Range of the Northern Spotted Owl. Portland OR.


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