Pterospora

The visible portion of Pterospora andromedea is a fleshy, unbranched, reddish to yellowish flower spike (raceme) {{convert|15|–|170|cm|in|round=0.5|abbr=on}} in height,{{cite web |last1=Wallace |first1=Gary D. |title=Pterospora andromedea - FNA |url=http://floranorthamerica.org/Pterospora_andromedea |website=Flora of North America |access-date=28 March 2024 |date=5 November 2020}} though it has been reported to occasionally attain a height of {{convert|2|m|ft|abbr=off|sp=us}}.{{cite journal |last1=Bidartondo |first1=Martin I. |title=The evolutionary ecology of myco-heterotrophy |journal=New Phytologist |date=August 2005 |volume=167 |issue=2 |pages=335–352 |doi=10.1111/j.1469-8137.2005.01429.x |pmid=15998389 |language=en}} The above-ground stalks (inflorescences) resemble an emerging asparagus spear in shape and are usually found in small clusters between June and August.{{cite book |last1=Heil |first1=Kenneth D. |last2=O’Kane, Jr. |first2=Steve L. |last3=Reeves |first3=Linda Mary |last4=Clifford |first4=Arnold |title=Flora of the Four Corners Region : Vascular Plants of the San Juan River Drainage, Arizona, Colorado, New Mexico, and Utah |date=2013 |publisher=Missouri Botanical Garden |location=St. Louis, Missouri |pages=494, 499 |url=https://archive.org/details/mobot31753003888887/page/n516 |access-date=30 April 2024}}{{cite book |last1=Dodson |first1=Carolyn |last2=Dunmire |first2=William W. |title=Mountain Wildflowers of the Southern Rockies : Revealing Their Natural History |date=2007 |publisher=University of New Mexico Press |location=Albuquerque, New Mexico |isbn=978-0-8263-4244-7 |pages=44–45 |url=https://archive.org/details/mountainwildflow0000dods/page/44 |access-date=2 May 2024}} The inflorescences are hairy and noticeably sticky to the touch. This is caused by the presence of hairs which exude a sticky substance (glandular hairs). The inflorescences are covered by leaves that have been reduced to scale-like structures known as bracts that are 2–3.5 centimeters long and 0.5–1 centimeter wide. The lower portion of the flowering stem is tightly covered in bracts and they become more widely spaced higher on the stalk.

File:PterosporaAndromedea5.jpg

The upper portion of the inflorescence has a series of white, yellowish, or rusty urn-shaped flowers that face downward.{{cite book |last1=Ferguson |first1=Mary |last2=Saunders |first2=Richard M. |title=Canadian Wildflowers Through the Seasons |date=1982 |publisher=Van Nostrand Reinhold |location=Toronto, Canada |isbn=0-7706-0018-2 |page=90 |url=https://archive.org/details/canadianwildflow0000ferg_h4r7/page/90 |access-date=2 May 2024 |language=en}} Each flower may have five sepals surrounding the base of the flower, which measure 4–6 millimeters long and are 2—3 millimeters wide. The fused petals (the corolla) measure 6–9 millimeters in length.

The fruit is a capsule with five lobes and 7–10 millimeters wide. Inside the capsules there are large numbers of very small seeds with, thin papery wings that are much wider than the seeds themselves. Plants exist for most of their life as a mass of branching roots that form round root balls. These root balls may be penetrated by the roots of other plants, but there are no vascular connections between them. At most, the total volume of a root ball is no more than 150–200 cubic centimeters. The inflorescence will grow from buds on roots which grow horizontally.{{cite journal |last1=Henderson |first1=Margaret W. |title=A Comparative Study of the Structure and Saprophytism of the Pyrolaceae and Monotropaceae with Reference to Their Derivation from the Ericaceae |journal=Contributions from the Botanical Laboratory of the University of Pennsylvania |date=1919 |volume=5 |issue=1 |pages=52, 76 |url=https://archive.org/details/contributionsfr10labogoog/page/n60 |access-date=3 May 2024 |publisher=University of Pennsylvania Press |language=English}}

Once fruiting is complete the flowering stems dry out and persist in the forest for a significant length of time.{{cite book |last1=Craighead |first1=John Johnson |last2=Craighead Jr. |first2=Frank D. |last3=Davis |first3=Ray J. |title=A Field Guide to Rocky Mountain Wildflowers : From Northern Arizona and New Mexico to British Columbia |date=1963 |publisher=Houghton Mifflin |location=Boston, Massachusetts |isbn=978-0-395-18324-3 |page=136 |edition=5th printing |url=https://archive.org/details/fieldguidetorock0000crai/page/136 |access-date=30 April 2024}}

The main plants that may be confused with Pterospora andromedea are the mycoheterotrophic orchids in genus Corallorhiza, commonly called the coral roots. However, their flowers are {{plantgloss|bilateral|bilaterally}} symmetrical, not {{plantgloss|regular}} like those of pinedrops.

P. andromedea, like all members of Monotropoideae, is a mycoheterotroph. This is a form of carbon acquisition that is parasitic on fungal organisms and epiparastic of photosynthetic plants which are symbionts to the fungal host. Because P. andromedea is achlorophyllous{{citation|last1=Cummings|first1=Michael P.|title=Pigment composition of putatively achlorophyllous angiosperms|year=1998|journal=Plant Systematics and Evolution|last2=Welschmeyer|first2=Nicholas A.|volume=210 |issue=1–2 |page=105 |doi=10.1007/BF00984730 |bibcode=1998PSyEv.210..105C }} this relationship is an obligate symbiosis for it, but is not ubiquitous in the fungal host. All monotropoideae are host specific to a select few fungal counterparts which in turn makes them specific to the photosynthetic organism associated with their fungal host. In the case of P. andromedea fungal host specificity leans heavily towards Rhizopogon salebrosus{{Cite journal|last1=Dowie|first1=Nicholas J.|last2=Grubisha|first2=Lisa C.|last3=Burton|first3=Brent A.|last4=Klooster|first4=Matthew R.|last5=Miller|first5=Steven L.|date=2017-01-02|title=Increased phylogenetic resolution within the ecologically important Rhizopogon subgenus Amylopogon using 10 anonymous nuclear loci|journal=Mycologia|language=en|volume=109|issue=1|pages=35–45|doi=10.1080/00275514.2017.1285165|pmid=28402794|s2cid=12476105|issn=0027-5514}} in the western distribution and Rhizopogon kretzerae{{Cite journal|last1=Grubisha|first1=Lisa C.|last2=Dowie|first2=Nicholas J.|last3=Miller|first3=Steven L.|last4=Hazard|first4=Christina|last5=Trowbridge|first5=Steven M.|last6=Horton|first6=Thomas R.|last7=Klooster|first7=Matthew R.|date=July 2014|title=Rhizopogon kretzerae sp. nov.: the rare fungal symbiont in the tripartite system with Pterospora andromedea and Pinus strobus|journal=Botany|volume=92|issue=7|pages=527–534|doi=10.1139/cjb-2013-0309|issn=1916-2790}}{{Cite journal|last1=Hazard|first1=Christina|last2=Lilleskov|first2=Erik A.|last3=Horton|first3=Thomas R.|date=2011-10-12|title=Is rarity of pinedrops (Pterospora andromedea) in eastern North America linked to rarity of its unique fungal symbiont?|journal=Mycorrhiza|volume=22|issue=5|pages=393–402|doi=10.1007/s00572-011-0414-y|pmid=21989709|s2cid=3259872|issn=0940-6360}} in the eastern distribution but broadly seems to be ubiquitous symbionts with Rhizopogon subgenus Amylopogon.{{cite journal |last1=Cullings |first1=K. W. |last2=Szaro |first2=T. M. |last3=Bruns |first3=T. D. |title=Evolution of extreme specialization within a lineage of ectomycorrhizal epiparasites |journal=Nature |date=January 1996 |volume=379 |issue=6560 |pages=63–66 |doi=10.1038/379063a0|bibcode=1996Natur.379...63C }} Rhizopogon species also exhibit high host specificity and sub-genus Amylopogon is primarily associated with the Pinus genus. Fungal exoenzymatic activity has been shown to be required for seed germination of P. andromedea however the requisite enzymes are not exclusively produced within subgenus Amylopogon indicating that seed colonization by fungi outside of the observed host specificity is possible however ecologically restricted by some currently unknown mechanism.{{Cite journal|last1=BRUNS|first1=THOMAS D.|last2=READ|first2=DAVID J.|date=2000-11-27|title=In vitro germination of nonphotosynthetic, myco-heterotrophic plants stimulated by fungi isolated from the adult plants|journal=New Phytologist|volume=148|issue=2|pages=335–342|doi=10.1046/j.1469-8137.2000.00766.x|issn=0028-646X|doi-access=free}} Though often described as a parasitic relationship, there is some evidence that it may be a mutualistic partnership.{{cite journal |last1=Li |first1=Jianhua |last2=Corajod |first2=Jeffrey |last3=Vander Stel |first3=Holly |last4=Homkes |first4=Austin |title=The Mycorrhizal System of Pterospora Andromedea (Pine-Drops) in West Michigan Inferred from DNA Sequence Data |journal=The Michigan Botanist |date=2011 |volume=50 |issue=3 |pages=129–136 |url=https://quod.lib.umich.edu/m/mbot/0497763.0050.303/--mycorrhizal-system-of-pterospora-andromedea-pine-drops?rgn=main;view=fulltext |access-date=1 May 2024 |language=en |issn=2166-4374}}

File:5 Pterospora andromedea - John Lindley - Collectanea botanica (1821).jpg's Collectanea botanica]]

Pterospora andromedea was first scientifically described by Thomas Nuttall in 1818. He based his work on specimens collected by Charles Whitlow in Canada near Niagara Falls. Amos Eaton published a description of the plant as Monotropa procera at almost the same time, but available evidence shows that Nuttall's publication was before Eaton's.{{cite journal |last1=Wallace |first1=Gary D. |title=A Question of Priority: Pterospora andromedea Nuttall vs. Monotropa procera Torrey ex Eaton (Monotropoideae, Ericaceae) |journal=Aliso: A Journal of Systematic and Floristic Botany |date=1 January 2022 |volume=40 |issue=1 |pages=57–63 |doi=10.5642/aliso.BWQH1814 |url=https://scholarship.claremont.edu/aliso/vol40/iss1/3 |access-date=28 March 2024 |issn=0065-6275|doi-access=free }} {{As of|2024}} Pterospora andromedea is the only species in the genus, making it a monotypic taxon.{{cite POWO |id=27135-1 |title=Pterospora Nutt. |access-date=1 May 2024}}

Pterospora has consistently been shown to be more closely related to Sarcodes than any other member of the Monotropoideae.{{cite journal |last1=Bidartondo |first1=M. I. |last2=Bruns |first2=T. D. |title=Extreme specificity in epiparasitic Monotropoideae (Ericaceae): widespread phylogenetic and geographical structure |journal=Molecular Ecology |date=September 2001 |volume=10 |issue=9 |pages=2285–2295 |doi=10.1046/j.1365-294X.2001.01358.x|pmid=11555270 |bibcode=2001MolEc..10.2285B }}

The genus name is derived from the morphology of the seeds which have narrow flaps of tissue on the side and therefore appear winged: pteron (Gr.) = wing, spora (Gr.) = seed. The specific name andromedea derives from the resemblance of the flowers to those of another genus in the Ericaceae, Andromeda.

In English it is known by the common name "pinedrops" and the similar "woodland pinedrops" and "giant pinedrops".{{cite book |last1=Roberts |first1=Rhoda N. |last2=Nelson |first2=Ruth Ashton |title=Mountain Wild Flowers of Colorado and Adjacent Areas |date=1967 |publisher=Denver Museum of Natural History |location=Denver, Colorado |pages=6, 34 |url=https://archive.org/details/mountainwildflow00robe/page/34 |access-date=1 May 2024 |language=en}}{{cite book |last1=Shaw |first1=Richard J. |last2=On |first2=Danny |title=Plants of Waterton-Glacier National Parks, and the Northern Rockies |date=1979 |publisher=Mountain Press Publishing Company |location=Missoula, Montana |isbn=978-0-87842-114-5 |page=146 |url=https://archive.org/details/plantsofwaterton00shaw/page/146 |access-date=1 May 2024 |language=en}} Because Edwin James found the plant near Albany, New York it is also known as "Albany beechdrops".{{cite journal |last1=Clarke |first1=John M. |last2=House |first2=Homer D. |title=Report of the State Botanist for 1924 |journal=New York State Museum Bulletin |date=1925 |volume=266 |page=11 |url=https://archive.org/details/newyork26527019251926alba/page/n198 |access-date=1 May 2024 |publisher=Albany, N.Y. : University of the State of New York}} Another name is "giant bird's-nest".{{cite book |last1=Armstrong |first1=Margaret |last2=Thornber |first2=J. J. (John James) |author1-link=Margaret Neilson Armstrong |title=Field Book of Western Wild Flowers |date=1915 |publisher=C. P. Putnam's Sons |location=New York |page=360 |url=https://archive.org/details/ofwestefieldbook00armsrich/page/360 |access-date=1 May 2024}}

In the Salish–Spokane–Kalispel language this species is called "senchelep tapemis" which can be translated as "coyote's arrow".{{cite journal |last1=Hart |first1=Jeffrey A. |title=The Ethnobotany of the Flathead Indians of Western Montana |journal=Botanical Museum Leaflets |date=1979 |volume=27 |issue=10 |page=282 |url=https://archive.org/details/biostor-160967/page/n21 |access-date=30 April 2024 |publisher=Harvard University |location=Cambridge, Massachusetts |language=English}} In the Jemez language its name translates as "Elk Girl tree".{{cite thesis |last=Cook |first=Sarah Louise |date=1930 |title=The Ethnobotany of Jemez Indians |url=https://digitalrepository.unm.edu/cgi/viewcontent.cgi?article=1085&context=anth_etds |degree=Masters |page=26 |institution=University of New Mexico |access-date=21 May 2024}}

File:Pterospora_andromedea_4764.JPG, Washington).]]

Pterospora andromedea is native to North America from Alaska to central Mexico.{{cite POWO |id=582569-1 |title=Pterospora andromedea Nutt. |access-date=1 May 2024}} It has two populations, the larger in western North America and the other in the east, separated by the Great Plains. In Canada it is found in the western provinces of British Columbia, Alberta, and Saskatchewan and in the eastern provinces of New Brunswick, Ontario, Prince Edward Island, and Québec. In the western United States it is found widely in Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, South Dakota, Utah, Washington state, and Wyoming. It has also been reported in Sioux County, Nebraska and without county level distributions in Texas. America's eastern population is found in Michigan, New Hampshire, New York, Vermont, Wisconsin, and possibly in Pennsylvania.{{cite usda plants|symbol=PTAN2 |title=Pterospora andromedea |date=1 May 2024}} It grows or has grown in many Mexican states including Chihuahua, Coahuila, Durango, Hidalgo, Mexico City, Mexico State, Morelos, Nuevo Leon, Oaxaca, Puebla, Sonora, Tlaxcala, and Veracruz.{{cite web |last1=Hassler |first1=Michael |title=World Plants |url=https://www.worldplants.de/world-plants-complete-list/complete-plant-list |website=Synonymic Checklist and Distribution of the World Flora. Version 19.2 |access-date=1 May 2024 |date=17 April 2024}} It is also very rarely found in the highest elevations of Sierra de San Pedro Mártir in Baja California.{{Cite journal |last1=Rebman |first1=J. P. |last2=Gibson |first2=J. |last3=Rich |first3=K. |date=2016 |title=Annotated checklist of the vascular plants of Baja California, Mexico |url=http://sdplantatlas.org/pdffiles/BajaChecklist2016.pdf |journal=San Diego Society of Natural History |volume=45 |pages=139}}

In the western United States it is mainly found under conifer trees in areas with deep accumulations of needles and dry to moderately moist soils, but may also be found under some oak trees. More specifically they are found in Rocky Mountain Douglas-fir forests, ponderosa pine forests, the Sierra Nevada upper montane forest,{{cite book |last1=Horn |first1=Elizabeth L. |title=Sierra Nevada Wildflowers |date=1998 |publisher=Mountain Press Publishing Company |location=Missoula, Montana |isbn=978-0-87842-388-0 |page=4 |url=https://archive.org/details/sierranevadawild00horn_0/page/4 |access-date=3 May 2024 |language=en}} and under eastern white pines and balsam firs around the Great Lakes (especially on dunes that have become forested).{{cite book |last1=Weatherbee |first1=Ellen Elliott |title=Guide to Great Lakes Coastal Plants |date=2006 |publisher=University of Michigan Press |location=Ann Arbor, Michigan |isbn=978-0-472-03015-6 |pages=122–123 |url=https://archive.org/details/guidetogreatlake0000weat/page/122 |access-date=3 May 2024 |language=en}}

In addition to not photosynthesizing, pinedrops are also a protocarnivorous plant. The sticky stems trap small insects and enzymes break them down for nitrogen.

Though not a typical hummingbird plant, the broad-tailed hummingbird (Selasphorus platycercus) has been seen drinking nectar from pinedrop flowers.{{cite journal |last1=Waser |first1=Nickolas M. |last2=CaraDonna |first2=Paul J. |last3=Price |first3=Mary V. |title=Atypical Flowers Can Be as Profitable as Typical Hummingbird Flowers |journal=The American Naturalist |date=November 2018 |volume=192 |issue=5 |pages=644–653 |doi=10.1086/699836|pmid=30332579 |hdl=10150/631593 |hdl-access=free }}

In 2019 NatureServe evaluated the conservation status species and as "globally secure" (G5), a species that is not significantly declining over the whole of its range. At the state and provincial level it also found it to be "secure" S5 in British Columbia and "apparently secure" (S4) in Montana. However, it is "vulnerable" (S3) in Wyoming, Nevada, and Alberta. In the rest of the west they evaluated it as "imperiled" (S2) in Nebraska and "critically imperiled" (S1) in Texas and Saskatchewan. In the eastern part of its range it imperiled or critically imperiled in every state and province with the exceptions of Massachusetts, where the species was not evaluated, and Prince Edward Island, where it is possibly extirpated. It is imperiled in Michigan, Ontario, Quebec and critically imperiled in New Brunswick, New Hampshire, New York, Vermont, and Wisconsin.

The seed stalks are occasionally collected to be used as long lasting ornaments in dry floral arrangements. Though the flowers are considered desirable by plant collectors,{{cite book |last1=Lindley |first1=John |title=Collectanea Botanica, or, Figures and Botanical Illustrations of Rare and Curious Exotic Plants |date=1821 |publisher=Richard and Arthur Taylor, Shoe-Lane |location=London |page=5 |url=https://archive.org/details/mobot31753000796208/page/5 |access-date=3 May 2024 |language=Latin, English}} the very specific requirements of its fungal host make this plant practically impossible to transplant.{{cite web |last1=Trull |first1=Sue |title=Woodland Pinedrops |url=https://www.fs.usda.gov/wildflowers/plant-of-the-week/pterospora_andromedea.shtml |website=Plant of the Week |publisher=U.S. Forest Service, United States Department of Agriculture |access-date=3 May 2024 |language=en}}

• Corallorhiza

{{Reflist|30em}}

• {{Commons-inline|Pterospora andromedea|Pterospora andromedea}}
• [http://www.calflora.org/cgi-bin/species_query.cgi?where-calrecnum=6934 Calflora: Pterospora andromedea]
• [https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=40272 Jepson Manual (TJM2) Treatment]
• [https://web.archive.org/web/20110525183140/http://www.newfs.org/docs/pdf/Pterosporaandromedea.pdf New England Plant Conservation Program: Pterospora andromedea Nutt.]
• [http://biology.burke.washington.edu/herbarium/imagecollection.php?Genus=Pterospora&Species=andromedea University of Washington, Burke Museum]
• [http://calphotos.berkeley.edu/cgi/img_query?query_src=photos_index&where-taxon=Pterospora+andromedea Calphotos Photo gallery, University of California]
• https://swbiodiversity.org/seinet/taxa/index.php?taxon=1012 Southwestern Biodiversity, Arizona - New Mexico Chapter - Pterospora andromedea]
• [http://www.tropicos.org/Image/100014760 photo of herbarium specimen at Missouri Botanical Garden, collected in Coahuila in 1990]

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Category:Monotropoideae

Category:Monotypic Ericaceae genera

Category:Flora of Canada

Category:Flora of the Northeastern United States

Category:Flora of the Northwestern United States

Category:Flora of the Southwestern United States

Category:Flora of California

Category:Flora of the Great Lakes region (North America)

Category:Flora of the Rocky Mountains

Category:Flora of the Sierra Nevada (United States)

Category:Parasitic plants

Category:Flora of Northwestern Mexico

Category:Flora without expected TNC conservation status