Trial Run

A couple of weeks ago, Dr. Richard Sutton, professor of agronomy and horticulture at University of Nebraska-Lincoln, sent us an email to see if we'd like to try out a few different prairie plants on the green roof.  It's part of a larger research project (see their website here) trailing three species' survivability and persistence through dry periods, cold, and varying "soil" depths. 

Dr. Sutton was kind enough to send us not only the three species they're studying to try out on the Berry Prairie as part of the study, but also a fourth that he recommended would do well - and four of each species.  We're curious folk over here, so thought we'd give it a whirl.

New arrivals!

So here's what we received and planted:

Blue Grama (Bouteloua gracilis 'Conard')

This common short-grass prairie species was already planted on the green roof, but this particular variety ('Conard') is new to us.  Blue grama is a staple in Wyoming, and on the Berry Prairie too - we have over 900 individual plants of this species planted!  Let's see how this variety does.

Hairy Grama (Bouteloua hirsuta)

This cousin to Blue grama is found in the very eastern edge of Wyoming (see the Rocky Mountain Herbarium site).  Although it's not found within 30 miles of Laramie, as all of our other plants, it is an interesting grass.  See how the anthers dangle below the flower of the grass?  That's what makes it "hairy."

Hairy grama flower

Blue grama flower

Sun Sedge (Carex inops heliophila)

This sedge is found through the eastern third(ish) of the state - see the map here.  It's an early season sedge so is often one of the first plants to green up in the spring (Forest Service website). 

Sand Dropseed (Sporobolus cryotandrus)

This grass is a warm weather (late summer) bloomer that prefers dry, usually sandy areas.  It's found throughout North America.  [Prairie dropseed is my personal favorite of the Wyoming grasses, but perhaps this one will win my heart.]

Photo from Prairie Moon Nursery

 
 
Stay tuned for their progress.

Written by Brenna Marsicek, Biodiversity Institute

Paintbrush Update

About a month ago I planted 29 Castilleja seedlings, 19 of which are Castilleja sessiliflora and 10 are Castilleja integra. Each Paintbrush was paired with one of three different host plants: Fringed sage (Artemisia frigida), Firecracker Penstemon (Penstemon eatonii), and Rocky Mountain Penstemon (P. strictus).

All of the host plants seem to be doing very well. Some of the initial seedlings planted do not look very healthy; however, if you take a closer look there appears to be a substantial amount of new growth underneath. So far the Castilleja sessiliflora paired with the Rocky Mountain Penstemon look the best. This pair has some new growth and others that look about the same. The total number of dead Castilleja is 3, all are Sessiliflora and all three have a different host plant. We do not know the reason for these deaths, but transplantation is often very stressful for plants. There is not enough information to say that one host plant works better than another at this point.

I had the opportunity to transplant wild Paintbrush from my parents’ property in Monument, Colorado. This experiment will allow us to see how robust these plants are and if transplanting is an option for growing. My parents dug up associated plants, as well, but we can’t tell which plant is the host (if any). These transplanted Paintbrushes gave the garden color and attracted pollinators as well as viewers. It gave the garden the aesthetics it was lacking. They flowered for about a month; a few are still flowering and hopefully they will all return next year. We are not advocating that anyone collect paintbrush or any other wildflower from land not your own! Because one species of Paintbrush (C. linariifolia) is Wyoming’s state flower, it is protected, so in this state it should not even be picked. 

The Colorado flowers are fading.  We think these are C. integra.

The third experiment I am trying is to grow Paintbrush from seeds. It takes Castilleja seeds around 60-90 days to germinate and requires a cold treatment to break dormancy. We placed Castilleja angustifolia and Castilleja chromosa seeds in the refrigerator on April 11, 2013, and they are just now germinating. I planted them in a plug tray to see if they will sprout, and then hopefully plant them outside. 

These tiny seedlings are C. chromosa, one week after planting.

All of these plants are found near the South doors to the Berry Center. It is not very colorful at this time because they are not flowering. Come by and check them out for yourself and see if you can tell the difference between the Castilleja sessiliflora and the Castilleja integra.

 Written by Jenna Ramunno, Biodiversity Institute

The Germinator

As you may know, a number of the plants on the Berry Prairie were grown from seed, specifically for use on the green roof.  Starting wildflowers from seed can be as easy as throwing them on the soil.  More often, however, it takes careful and strategic processes that range from refrigeration to scratching to freezing to burning.  The post below gives an overview of the many ways we germinate seeds, including as it relates to Jenna's Indian Paintbrush project.

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Seed Germination

Not every seed will grow as soon as it is in the ground. Seed dormancy is the failure of a viable seed to germinate under adequate environmental conditions; a seed will germinate after dormancy is overcome or broken. Seed dormancy is desired in the wild because plants depend on nature for survival. If a seed germinates but the conditions are not right for growth the seedling will die. Some seeds require stratification while others require scarification.

Penstemin eriantherus blooming on the Berry Prairie.

Scarification is where the seed coat is scratched to loosen the covering. The seed will not germinate until the seed coat is altered physically, to make it permeable to water. This happens in different ways in nature. One way is by a seed falling, or being scratched on a rough surface. Another example of scarification can occur is when it passes through the digestive tract of various animals. Strawberries and raspberries are an example. Frugivores, like bears, digest the fruit pulp, but the seed coat passes through the digestive system and the acid in the digestive track breaks down the seed coat making it ready for germination.

Castilleja chromosa seed just starting to germinate
after 2 months in the fridge.

Stratification is when a seed undergoes a cold or hot treatment to break dormancy. This happens in nature when it snows in the winter. Many of our native wildflowers require stratification. For example, when Karen Panter started Penstemon eriantherus for the Berry Prairie, she kept the moist seeds in the refrigerator for up to three months before planting! Seeds can be put in moist soil or perlite, or even just in plastic bag with a bit of water, before refrigeration. We used this last technique to germinate Indian paintbrush seeds—read more about that soon.

Another way to stratify seeds is to plant them during the late autumn or winter, and leave the pots outside over winter. Some plants will germinate even better the second year, after overwintering twice.

The fires that occurred this summer and last in Colorado have created a lot of destruction. Even though it does not seem like it, the fires have also created growth. The heat of the fire actually weakens the covering of some kinds of seeds enough to enable it to intake moisture and germinate. This is common for pinecones; they are tightly shut and the heat allows them to open and release the seeds.

The wildflower Corydalis aurea is common after wildfires.
Fire stimulates its long-lived seeds to germinate.

Written by Jenna Ramunno, Biodiversity Institute