Because everyone knows April means Opening Day!
Of field season!
But when I do, you'd better believe they're destined for this blog.
Forty degrees (F), windy, and barely recovered from some sort of virus wasn't exactly the day out I had dreamed about all winter, but I'll take what I can get.
I went to check on my prairie experiment at the Lux Arbor Reserve, part of the Kellogg Biological Station, an off-campus Michigan State research facility. It's actually pretty hard to find information about the history of Lux Arbor, but my understanding is that the land belonged to the heir to some sort of industrial fortune. Wouldn't you name your personal hunting estate something posh like "Lux Arbor" to impress your posh friends?
One thing I know for sure is that the very long field that houses my prairie experiments (and yet still has room for 10 more) was the air strip for Mr. Arbor's private use. How divine to take a jaunt in the prop with your ol' chum Lux! (Queue "elegant dinner party" laughter, Archer fans.)
I know nobody's name was "Lux Arbor" but I really prefer that my Gatsby-esque mystery fellow has a name while I'm pondering all that once went on in the area around my field site. It's like Lex Luthor. Lux Arbor. Anyway...
In this experiment, I'm trying to find out what happens when you plant identical prairies in different years. This may seem so straightforward as to be completely uninteresting, but hear me out!
Plenty of prairie restorations turn out great. The practitioners prep the site, they sow the seeds, and the prairies grow. End of story. Plenty of other restorations, however, don't turn out well at all. The practitioners prep the site, they sow the seeds, and then something else grows that looks more like a weedy mess. Why no prairie you may ask? Well, it must have been a bad year!
This is common in an anecdotal sense, which means it's just screaming for some science to figure out the details. So my question is, are there really bad years? And if so, what about them is bad? Does it just depend on how much it rains, or can a booming sparrow population swoop in and eat all the sown seeds? Questions like these just raise more questions, like, which species will be affected, and when? Also, how are they affected-- through seed mortality, altered germination rates, seedling mortality... there are so many questions to be asked about this "bad year" concept, and I'm just cracking the surface.
My two experiments at Lux Arbor are testing two things. 1. Year. What happens when you sow an identical prairie three years in a row? And 2. Rainfall. What happens when the newly sown prairie gets different amounts of precipitation? For the latter experiment, I built rain-out shelters last year that blocked and collected all the rain from above the prairie plots I planted, and then watered them to mimic high, low, or average amounts of rain. I'll repeat both of these year (where the plots just get ambient conditions) and precipitation (with the rain-out shelters) treatments this year (2015) and next (2016).
It's not time to build rain-out shelters for this year quite yet (stay tuned!), but my 2014 plots-- which received the rain treatments last year-- are already starting to grow!
That is, the weeds are starting to grow.
Never in my life have I been so sensitive to the fact that all the plants that turn green first in the spring are exotic. The bluegrasses (i.e., your lawn), the dandelions, the ornamental shrubs-- they're all already green right now, but the native species are not. Think about this next time you're driving through town or on the highway, admiring the green roadsides. Heck, I think some of my daffodils are almost done blooming! (Side note: I just looked up Daffodils to confirm they were exotic before I said this-- did you know their real name is Narcissus?)
Some exotic plant species that are also invasive (not all exotics are invasive, but nearly all invasives are exotic) actually use this to their advantage. It's called temporal priority-- temporal meaning seasonal, and priority meaning they get the goods before the natives have even shown up to the party. For example, they can take advantage of light where there will later be shade from natives, or start pulling up soil nutrients before the natives have a chance. It's one of their many "invasive" characteristics that makes them nasty (the technical term for hard on native species, and hard to get rid of).
It's all exotic. Mostly spotted knapweed (Centaurea stoebe)
One of the major ways that year effects-- precipitation especially-- might influence a new prairie is through the weed community. In other words, if the weeds grow differently when rainfall patterns are different, maybe that's what causes the reaction in the prairie, rather than a direct effect of rain. This is probably not a big deal when weeds are benign (things like garden clovers), but when they're invasive species like spotted knapweed, the prairie plants have no choice but to suffer accordingly.
Keep this on the down-low, internet. Maybe this will be my groundbreaking dissertation discovery. Weeds ruin prairie restorations! Shh!
My opening day surveys involved identifying all the green plants in each plot, and quantifying what percentage of the plot each one covered. For example, look at the plot (inside the black edging) in the picture above. I'll make it easy and say you can pretend all the green is one species, Centaurea stoebe (close enough). What percentage would you say is CENSTO, what percentage is bare ground, and what percentage is litter (dead stuff from last year)? Now do that 47 more times, and you can go home. Oh, and you might need to stick your face against the ground to check whether that tiny grass seedling has auricles or not. Maybe bring knee-pads next time?
It wasn't all weeds, though!!
I am thrilled to report that a handful of prairie species that I sowed were, in fact, growing!
Hover your mouse over these to get the caption:
Yes that's right, I'm still taking blog pictures with my iPhone. I'm sorry, okay?
I actually assume this curly-q insanity will flatten out and just be some plain old grass that isn't particularly exciting. But for now, I'm pretty pumped that something this cool ended up not only in my site, but in a plot, on a survey!
I'm glad I braved the cold to check on my weeds.
Plant identification suggestions or corrections warmly appreciated.
Happy field season!