Saturday, March 31, 2012

Ostrich fern and Sensitive fern dropping spores

What:  Sporangia on fertile fronds of both sensitive fern (Onoclea sensibilis) and ostrich fern (Matteuccia struthiopteris) open and drop their spores early in the spring.

Ecological notes: Of our local ferns, only a small handful have the spores located on separate fronds (called fertile fronds). Examples include sensitive fern, ostrich fern, royal fern, and sort of intermediate fern. All of these are adapted to wet areas. Could be that having separate fronds allows them to protect the spores throughout the winter in the modified pinnae (that form the little balls) and then as the snow melts, drop their spores to be dispersed in the spring runoff to other spots where water pools.

Where: I find ostrich fern in sandy, but moist and enriched soils with moderate to high pH. Sensitive fern tends to like it wetter than ostrich fern (and therefore in more clay-ey, silty soils than ostrich fern). This patch is on a slope with a high water table.

Other notes: To tell the two species apart, ostrich fern has much larger more robust, wider spreading fertile fronds than the more delicate sensitive fern fronds. Ostrich fern also has fronds that are born out of a small dense cluster. In winter, you will readily notice the small dark knobs sticking out of the ground in a patch of ostrich fern. Sensitive has single blades that come out of the ground (these are often clumped loosely), but don't come out of the ground from a single point so you won't see the same lumpiness to the ground.

Shrubs bursting

What: Leaves on Red elderberry (Sambucus racemosa), Tartarian honeysuckle (Lonicera tartarica), and Black cherry (Prunus serotina), respectively, bursting.

Ecological notes: Trees in the understory are often the first to leaf out. They risk hard frosts (like that 19 degree night we had the other day) in order to photosynthesize before the canopy trees leaf out. As a generalization, larger trees can store more energy relative to body size so they have a little more of a buffer on how long they can overwinter, plus they're in prime real estate during the summer to make for lost time photosynthesizing.

Where: All over Burlington the green is starting to return. First in the grasses and celandine poppies, then in the shrubs. By now the ostrich fern is starting to pop up as are the wild leeks.

Other notes: Already I've seen blossoms on red elderberries (at Red Rocks in South Burlington). My ornamental elderberries (Sambucus canadensis) haven't put out flowers yet and the emerging leaves do not have the same reddish tinge to them as the wild ones do. The red is caused by the same pigments that make the leaves red in the fall (non-photosynthetic vacuolar pigments called anthocyanins). It's possible that these require little energy investment chlorophyll takes lots of energy to produce) and the plant can produce the structural part of leaves initially and then chlorophyll once the fear of frost is reduced.

Friday, March 30, 2012

Siberian Squill

What: Siberian squill (aka Scilla siberica) is always the first flower to pop up in early spring (last year April 2 they first appeared). This little patch in my backyard actually came up about a two weeks ago (March 17)! The little blue flowers (in the same family as asparagus) are up before most insects, so pollination is done largely by overwintering adults of members of the bee family (and on warm days).

Ecological notes: While this plant has escaped from cultivation, it's still a nice addition to my backyard - telling me when the ground has thawed (I see it around the same time I begin to hear the earthworms crunching the leaves at night). It's also a spring ephemeral, meaning that it's whole life cycle takes place before the trees leaf out. Otherwise it's dormant and spends the rest of spring, summer, and winter as a seed or bulb.

Where: I have sandy soils that seem to accommodate this little guy quite well. They're perennial (like lilies, they have bulbs - not sure if they're edible). Because they rely on insects for pollination I would suspect they rely less on seeds than on vegetative reproduction - a cold spring would mean an absence of flying insects.

Other notes: The leaves seem waxy, but are incredibly week and will yellow pretty quickly if I walk over them. It's name probably derives from the Greek word for the plant (since the word was used in latin to convey shrimp like). The genus is Eurasian, so this plant's name is derived from other similar plants that might more closely resemble shrimp. Maybe the dangling flower was reminescent of some squid-like critter?

Tuesday, March 27, 2012

Beavers in Centennial Woods

What: One of the beavers wound up passing out on the bank of Wool Pullery Brook and slept there for 10 hours! I had watched it the night before and caught it on my game cam. I figure it was active for about 12 and a half hours straight, plus the three previous days had been super warm. Like everything else it was probably just enjoying the first taste of summer in March!

Ecological notes: While the videos are from last Friday, I was back out at the pond tonight. The weather is about 60 degrees colder now and a thin sheet of ice is blanketing the pond. I watched as the beavers actively cleared out the ice by putting their heads above it and pushing down. It was funny to watch as one of the beavers had chunks of ice stuck to its nose.

Where: Wool Pullery Brook at the upper terrace of the beaver pond (there are now three terraces). Still haven't their upper den, but I think it's right next to the upper dam.

Other notes: The beavers seem to start being active around 7pm, an hour or so before it's dark.

Sunday, March 25, 2012

Wood Frog eggs

What: Wood frogs (Lithobates sylvaticus) have been singing in Centennial Woods for about a week now (sounds like a bunch of ducks quacking). Yesterday I was out and found several egg masses in various stages of development.

Ecological notes: Along with spring peepers, wood frogs are one of our first amphibians to emerge in the spring. Spending their time literally frozen for the winter, they revive with warming temperatures and head from their upland overwintering sites down to their breeding ponds. With the upcoming cold weather, this should slow down the development of the eggs considerably, and the tadpoles won't emerge for another 10 days or so.

Where: Wood frogs breed in shallow seeps, cattail marshes, and vernal ponds (particularly fond of the latter) and just about anywhere else there aren't fish to eat their tadpoles.

Other notes: There was a couple of inches of water on top of a thick sheet of ice at the bottom - must have frozen all the way through this winter. The little "pool" of water is at the bottom of a seep and slowly filters into Centennial Brook. The water on top is probably from increased flow of water as frozen ground water has been melting.

Monday, March 19, 2012

Coltsfoot blossoms

What: First coltsfoot (Tussilago farfara) blossoms of the year. Along with all the other harbingers of spring, this always signals the regreening of the ground (maybe the end of sugaring, too?). The flowers come up first and look similar to dandelion flowers. Note, however, the leaflets ringing the stalk and lack of leaves.

Ecological notes: Like dandelions, they have perennial roots, which allows them to sprout earlier in the year. They also spread vegetatively (by roots) so I find them in dense clusters. The leaves will come up in a few weeks. Not sure if these jumped the gun with all that warm weather. It's 19 degrees as I write this.

Where: Look for coltsfoot growing in gravely ditches, sandy streambanks and other "waste places." I found this beautiful specimen growing alongside Pond Rd in Shelburne while looking for amphibian sign.

Other notes: The subtle flowers were easily overlooked while searching for amphibians. We heard a few spring peepers peeping in the 80 degree heat (record high). Plus we saw lots of Eastern Newts swimming in the shallows and heard muskrats making their whining mating noises.

Thursday, March 15, 2012


Postings are related to the seasons and will hopefully help you (and me) understand some of the phenological events happening on the land. I'll cover the common (blue jays, dandelions) and the overlooked (ambush bugs, velvet leaf). Feel free to share comments, ask questions, and recommend topics for me to cover.