I have a hard time with shrubby species. They just don't stand out to me like herbaceous plants or giant trees. As such, my identification skills for this group of medium-sized woody plants are subpar. However, every once in a while I find something that I can't let go. Usually its a species with a trait that really stands out. This is how I came to know buffalo nut (Pyrularia pubera). Its unique inflorescence was like nothing I had ever encountered before.

There is good reason for my unfamiliarity with this species. It is largely restricted to the core of the Appalachian Mountains, although there are records of it growing on Long Island as well. Regardless, it is not a species I grew up around. The first time I saw its flowers I was stumped. I simply couldn't place it. Luckily its unique appearance made it easy to track down. I was happy with buffalo nut for the time being but I was surprised yet again when I sat down for a chat with someone who knows woody species much better than I do.

As it turns out, buffalo nut belongs to the sandalwood family, Santalaceae. This makes it a distant cousin of the mistletoes. Like most members of this family, buffalo nut lives a parasitic lifestyle. Although it is fully capable of photosynthesis and "normal" root behavior, under natural conditions, it parasitizes the roots of other tree species. It doesn't really seem to have a preference either. Over 60 different species hailing from 31 different families have been recorded as hosts.

When a buffalo nut seed germinates, it starts by throwing down a taproot. Once the taproot reaches a certain depth, lateral roots are sent out in search of a host. These roots "sniff out" the roots of other species by honing in on root exudates. When a suitable root is found, the buffalo nut root will tap into its host using specialized cells called haustoria. Once connected, it begins stealing water and nutrients. Buffalo nut roots have been known to travel distances of 40 feet in search of a host, which is pretty incredible if you ask me.

It is easy to look down on parasites. Heck, they are largely maligned as free loaders. This could not be farther from the truth. Parasites are a healthy component of every ecosystem on the planet. They are a yet another player in a system that is constantly changing. What's more, the presence of parasites can actually increase biodiversity in a system by keeping certain species from becoming too dominant. Buffalo nut should not be persecuted. Instead it should be celebrated. It is yet another species that makes the Appalachian Mountain flora so unique.

Further Reading: [1] [2]

Photo by Vernon Jenewein Vljenewein Public domain

While living and working in Wyoming, I had the chance to meet so many amazing plant species. Many of these were quite unique to the high desert environments where we were assigned. Countless hours were spent searching large swaths of land rarely visited by humans. One species of plant managed to elude me during my time in that beautiful part of the country. The plant is incredibly rare and thus a focus of federal protection and restoration efforts.

Based on first impressions, blowout penstemon (Penstemon haydenii) may look like any other penstemon. The similarities stop there and indeed, this is one of the most unique species of penstemon I have ever heard of. Originally it was only known from a few locations in the Sand Hills of Nebraska. Recently, a few populations were discovered in Wyoming but it is by no means common.

As its common name suggests, P. haydenii is a specialist of blowouts. These depressions in the sand are caused by blustering winds that carve out and remove all vegetation. Most plants cannot survive in these conditions. There is very little water, the sands are constantly shifting, and as the wind kicks up sand at high speeds, the abrasive force can actually cut down frail vegetation. This is where P. haydenii excels.

It has a thick, waxy cuticle covering its stem and leaves that protect it from this sandblasting effect as well as drought. The seeds of these species are dispersed by wind and have extreme longevity in the soil. They can remain dormant for decades until the right conditions are present for them to germinate. P. haydenii seeds need at least 2 weeks of steady moisture and lots of abrasion from sand in order to break dormancy. Research has shown that these conditions are only ever present one out of every 8 to 10 years. As a result, P. haydenii has a debilitatingly small recruitment window.

This rarity has placed it on the endangered species list. Ironically, the very regulations that were put into place to control range degradation by cattle ranchers may have caused serious declines in this species. It was once common practice to over-graze the land where P. haydenii is found and as a result, vegetation became sparse. This increased the likelihood of blowout formation, which favored P. haydenii. Fire suppression is another threat. Regular fires help kill back vegetation that would otherwise outcompete P. haydenii.

With droughts on the increase and human activities expanding into areas where the few remaining populations of P. haydenii occur, the future of this strange little endemic is uncertain. There has been a lot of effort to save and restore this species numbers but it is by no means the end of the story. Only time will tell...

Photo Credit: Vernon Jenewein Vljenewein

Further Reading:
http://plants.usda.gov/core/profile?symbol=peha12

http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=Q2EX