Mac Is Back!

Day 258: Mac is back! Last year, my "pet" Corallorhiza maculata was nipped off by something (deer, slug, squirrel...I don't know who the culprit was) when it was only about six inches tall. This year, she's making up for lost time by putting up two stalks which, as you can see here, are just beginning to flower. I've done my best to protect the plant by installing an 18" high chicken-wire fence around it, staked to the ground with short lengths of bamboo garden wand. That said, the Corallorhizas are amazingly resilient. Many can remain in a dormant state for years without ever breaking ground. The key lies in the plants' companion fungi. Each species of Coralroot has one or more specific "companion" fungi on which they depend. The fungi break down nutrients in the soil which can then be taken up by the plant. Currently, there is debate among botanists as to whether this is parasitism (in which case the fungus derives no benefit from the plant) or true mycoheterotrophy (a cooperative arrangement in which plant and fungus provide some requirement). I hold with the latter view on the hypothesis that if a long-term partnership has evolved, then it must in some way be advantageous to both parties. Despite the fact that we haven't identified what that exchange might be, absence of evidence does not negate the possiblility of it existing in some way we cannot detect. Good science is inquiry, not denial.

Yellow Mac

Day 232: I had gone looking for Northern Coralroot (Corallorhiza trifida) in the usual places and wasn't too surprised when I didn't find any, given the wetter and colder spring weather. What did surprise me, though, was the absence of Corallorhiza maculata, the species which grows in my back yard. I was on my way back to the car when something yellowish caught my eye on the hillside about thirty feet above me. "I swear that's Corallorhiza," I said as I began climbing up from the obscure pad of the Damn Trail, "but why is it so tall when there haven't been any other specimens in here? Can't be mertensiana. It's too early for mertensiana." Mertensiana is famous for its wide range of colour variations, maculata less so, although a striking yellow form occasionally occurs. Upon arriving at its side, I could see that the flowers were just beginning to emerge from some of the stems. I waypointed the specimen with my GPS, and will be keeping an eye on its development. If perhaps not the brilliant yellow variation I've seen elsewhere, I suspect it will prove out to be a yellow-tinged C. maculata.

Little Mac

Day 222: Just as the buds were swelling last year, some varmint came along and nipped the top off little Mac, my "pet" Corallorhiza maculata, bringing her season to an untimely end. However, this year, she's sending up two stems, and I've put a low cage of chicken wire around her which should deter deer, if not slugs. I suspect last year's culprit was a deer or elk because the tip was cropped off about eight inches from ground level and in any event, slugs are something I don't see often in my yard (curious, that, but I won't complain). The Corallorhizas are mycoheterotrophic, i.e., they rely on a fungal partner to convert soil nutrients into a form the plant can utilize. Here, I want to add that there is again a raging debate about whether this is true mycoheterotrophy or a parasitic relationship in which the fungus gains nothing from its partner. One school of thought insists that it is parasitism, but to my way of thinking, it only looks like parasitism because we haven't figured out what the fungus is getting out of the deal. Since some Corallorhizas are very particular about which fungal partner they will accept, logic tells me that the relationship is agreeable going both ways or it would not persist. Despite our inability to determine what benefit the fungus derives, it doesn't necessarily follow that it derives nothing. That kind of closed-minded attitude in science leads down a dead-end road.

Mac Is Back!

Day 200: I've been checking every few days for the last two weeks. Mac is back! My "pet" Corallorhiza maculata in the back yard is all of an inch tall. So far, only one stem has poked through the ground, but I'm hoping for more with good reason: I believe I may have identified this particular plant's mycorrhizal associate. C. maculata is a mycoheterotroph, and as such is a bit less discriminating than some of the rarer species. It associates with a wider range of fungi, as opposed to C. trifida or C. striata which are more specific in their partnerships. My Mac may be working in tandem with Ramaria acrisiccescens, a common coral fungus which goes by the unlovely common name of "Blah Coral." Last fall, several lines of R. acrisiccescens fruited in her immediate vicinity along the shadowy edge of my wooded strip. Given the abundance of the fungus, Mac may be able to start a family of her own.

Mac Pods

Day 329: Mac pods! No, not an advertisement for Apple products, but rather the seed pods of my pet Corallorhiza maculata. If you will recall, I was lamenting the fact that I couldn't get to my beloved mycoheterotrophic plants in the spring until one day I discovered that they'd come to me in the person of Mac, who cropped up unexpectedly in my back yard. I put stakes and flagger tape around her for protection, but even so, her stem was somehow bent but not fully broken just below the inflorescence. One must take into consideration that any plant which can survive a dormancy of 25-30 years must be pretty tough. Mac refused to give up and, with the help of her mycoheterotrophic partner fungus (type unknown), withdrew sufficient nutrition from the soil to bring pods to maturity.

A lot of requirements are at play in a mycoheterotroph's life cycle. It's not enough that she makes seeds, so fine that they are referred to as "dust seeds." Despite their microscopic nature, they rely on that critical, specialized fungal component to weaken their husks before germination can occur. Not only that, but the fungus helps break down soil nutrients into a form the growing plant can use. Without that fungal partner, Mac could not grow. Her seeds could not sprout. They would lay dormant until all the stipulations of her bio-contract were again met. It goes without saying that the rarity of a particular mycoheterotroph is weighted by the range of fungal partners it will accept. Fortunately, Mac is pretty broad-minded in that regard unlike, say, Cephalanthera. Will my yard be graced by her presence again next spring? We'll just have to wait and see.

Mac

Day 255: Lovingly nicknamed Mac, my "pet" Corallorhiza maculata is now just past her prime. She reached a substantial height of 20" and bore at least two dozen individual flowers.

Although the Corallorhizas form seed ("dust seed," extremely fine), they cannot germinate without the aid of soil mycorrhizae. The exact process is not well-understood. Some research has indicated that the mycorrhiza aids in breaking down the sheath surrounding the seed. What we do know is that the mycorrhiza is responsible for breaking down nutrients in the soil, converting them to a form which can be used by the plant. Interestingly, each species/subspecies of Corallorhiza is affiliated with a different fungal partner. Apparently my back yard suited Mac's needs. In the thirty years I have lived here, I have not found Corallorhiza on the property, but another thing we know about these marvelous mycoheterotrophic species is that they can disappear and lay dormant for more than 25 years, emerging again only when conditions are ideal. Given our relatively mild, wet winter, I had predicted that this year would be a boom year for mycoheterotrophs. My projection is being borne out not only near my home, but as friends and colleagues report in, the abundance is being noted throughout the Pacific Northwest. Due to COVID-19, I'm forced to enjoy most of them vicariously, but every day, rain or shine, I step out into my yard for a few minutes to tell Mac how beautiful she is.

Mycoheterotroph Magic

Day 242: You're going to scoff. I know that, and I know you're going to ridicule me for being about as unscientific as a person who calls themselves a scientist can get, but sometimes even the most anchored among us have to raise an eyebrow when things come together as if by magic.

During my friend Michael's pursuit of his degree in ecopsychology, he asked questions of me as a naturalist, as an animist and as a shaman. To me, the three terms form a well-balanced Venn diagram with me smack in the convergence zone. One question he posed was that, given my profound love of Nature, did I feel that Nature ever demonstrated love in return? I replied in the affirmative, but qualified my response by saying that naturally (if you will forgive the pun), this return would take a different form than human love, and might in fact manifest as something we would fail to recognize. That said, I cited at least one circumstance where it approached what we humans consider a demonstration of love, when Nature had seemingly expressed a sentiment toward me which, for want of a better phrase, I would express as gratitude. Love takes many forms among humans. Who can define it for anyone other than themselves?

My readers are aware of my passion for mycoheterotrophs, that group of plants which grow only in certain narrow ecologies, plants dependent on specific soil mycorrhizae, plants which cannot exist unless their complex requirements are met. Being in voluntary isolation has put dramatic constraints on my ability to "botanize." My expeditions are limited to walking distance from my home, but even so, this spring has brought a number of interesting finds: several slime molds, a plant not previously recorded on Park property, and a few scattered specimens of Corallorhiza maculata, one of my favourites. I mention the last specifically, because I had not observed them in this area previously, and I've done quite a bit of prowling about in the trailless woods in the last thirty years. I have been lonely for my mycoheterotrophs, more than for human company.

Yesterday afternoon, I walked out to the wooded strip between my property and the one adjacent to me, intending to pitch some radish leaves onto the unofficial compost pile. At the very margin, spotlighted in a sun-fleck as if to say, "Hey! Down here!" was a single stem of Corallorhiza maculata. The flowers were just beginning to open on the lower portion, a few maroon spots winking at me as I gaped in surprise. As I walked back to the house to get the camera, I burst into tears. If I couldn't go to my mycoheterotrophs, it seemed that at least one of them had come to me.

Mycoheterotroph Fix

Day 216: For me, the most painful part of voluntary isolation is not being able to go into the woods as much as I'd like, especially as the spring plants are emerging. However, I have been getting my botany fix during my morning walk, and on occasion, it has borne fruit which in turn led to some interesting email conversations with Arnie. One centered around the presence of Corallorhiza maculata at an unusual site: How did it get there? How is it managing to survive? As you may recall from previous posts, the Corallorhizas are mycoheterotrophs. More specifically, C. maculata (Spotted Coralroot) is an obligate mycoheterotroph. Unlike C. trifida, it lacks any trace of chlorophyll, and therefore depends entirely on soil mycorrhizae to break down nutrients into a form it can utilize. One would hardly expect it to pop up in a developed area only a few feet from pavement, and yet that's where I found eight or nine stems. Three or four others can be found in the surrounding forest, but that handful on the parking strip bother me, presenting a botanical puzzle I will never solve. Arnie and I have spent hours in discussion of the relationship between the rarer mycoheterotrophs and specific soil types which exist only in isolated pockets, and while C. maculata is not particularly rare, it does have fairly specific requirements for both soil and mycorrhizal partner. Further, the mycorrhizal components have requirements of their own. Some only grow where certain plant species are present. We refer to this as a species' "plant associations," and as good botanists, we use this knowledge as a tool to help us pinpoint where rare species may potentially occur. How, then, did dear little maculata pop up in a parking space which at some previous point had been scraped flat by a bulldozer? Yes, I'm getting my botany fix even on the short walks I take every morning, always the observer, always open to the questions the forest poses.

Corallorhiza Maculata

Day 237: Several species of Coralroot occur in Mount Rainier National Park. Of the more common ones, Corallorhiza maculata is my favourite. This mycoheterotroph displays a white lower petal marked with dark purple freckles and looks more like a tropical orchid than its cousins. Local specimens are generally shorter than C. mertensiana (the Coralroot most often seen), although in optimum growing conditions, its copper-coloured stems can reach heights of 30 cm.

Every year, I hope that somewhere in my travels, I'll find a specimen of C. striata within the boundaries of the Park. The only report of the species was subsequently proved in error. A specimen identified as C. striata was in fact C. mertensiana. Mycoheterotrophic plants are often very selective about their fungal associations, which no doubt accounts for the rarity of the species. Anybody know of research being done to determine which fungi are associated with specific Corallorhiza species?

Corallorhiza Maculata, Spotted Coralroot

Day 211: Following on the heels of Corallorhiza trifida, C. maculata is making an appearance in the lowland forests. Two days ago, I saw a newly emerged (unopen) specimen in a friend's woods. Yesterday, three surprised me in Pack Forest where I have never found them before.

The Corallorhizas are mycoheterotrophic species, which is to say that they lack chlorophyll and rely on the presence of specific ectomycorrhiza (fungi) which allow them to uptake nutrients from the soil. Not all of these associations have been discovered, but we do know that C. maculata is dependent on mycorrhiza of the genus Russula. The presence of Russulas in the autumn do not guarantee that an area will host Corallorhiza maculata, but if maculata is present in the spring, you can rest assured that Russulas will be evident later in the year at the same site.

There is a lesson in this, particularly for mushroom hunters: everything holds hands with something else in Nature. As strange as it may sound, over-picking of a mushroom species could lead to the extirpation or extinction of an Orchid. That's serious food for thought.

Penny Perspectives - Spotted Coralroot

Day 226: Arguably the showiest of the Park's four known Coralroot species, Corallorhiza maculata when seen from above is easy to gloss over as "a little brown plant." It's only when you take a closer look that the freckled face of this Orchid species reveals itself in all its speckled beauty. Another mycoheterotrophic species, C. maculata lacks chlorophyll and therefore relies on a mycorrhizal component's assistance in order to draw nutrients from the soil. Maculata can be quite common where it occurs, as it was where I found these near Westside Road, but since many mycoheterotrophs exist only in symbiosis with specific fungal species, its occurrence is likely to be patchy.