The silver maple tree at the bottom of my field flowered last week. The smooth lines of the branches that have been outline against the sky all winter are now fuzzy with the irregular edges of the tiny, open flowers. The red maples closer to the house, though, still have not flowered (although I understand from Jennifer Wood that some area bee keepers are starting to see bees returning to their hives with red maple pollen (and crocus pollen, too!)). In past years my red maples have regularly flowered by the third week of March. So this year’s very late appearance of their flowers is another sign of the stalled appearance of spring of 2015! The buds on the red maples, though, are swollen and look ready to pop open at any minute. We just need a couple of warm days to urge them on!
The tree buds are structures that encase and protect the embryonic flowers and leaves. The outer part of the bud is made of tough scales that form overlapping, shingle-like structures around the delicate leaf or flower growth tip. These bud scales keep out destructive insects and also insulate the inner tissues. These scales are really very tiny, very tough, modified leaves. Buds are classified as to whether they encase flowers (“floral” buds), or leaves (“vegetative” or, simply, “leaf” buds), or both floral and leaf embryonic tissues (“mixed” buds), and by their position on a branch (“terminal” buds are found at the end of a twig and “lateral” buds are found along the sides). On silver and red maple trees most buds are either floral or vegetative. The floral buds are larger and spherical and the leaf buds are smaller and more oblong. The floral buds are also typically clustered together in bunches on the twig. Over the winter I have watched squirrels nipping off the lateral buds on the red maple branches (they must be a welcome dietary supplement to balance out all of the sunflowers seeds they had been eating!). Most of the branches, though, were too thin for them to get out to the terminal buds, so I expect to see both flowers and leaves concentrated at the ends of tree branches this spring and summer.
As I said, the floral buds on the silver maple just opened last week and very soon, I hope, the red maple buds will open revealing the delicate clusters of red and yellow flowers. The tiny pollen grains from these flowers will then be spread mostly by the wind and by chance some will encounter ova in the ovaries of other flowers and accomplish the fertilization phase of the reproductive life cycle. The pollen is produced in prodigious amounts by these trees, and you can easily understand why. The probability of a given pollen grain, randomly dispersed through the atmosphere by the wind finding an appropriate ovum is infinitesimally small! To insure that fertilization occurs at all, the trees must fill the air with pollen. Human interactions with this pollen mass can generate allergic reactions in sensitized individuals. Hardwood tree pollen, in general, is a major spring allergy trigger. Dripping noses and red eyes, unfortunately, come with the season.
Once an ovum is fertilized it will develop into the maple tree’s distinctive winged seeds (their “samara”). These “maple keys” will, by early May or so, form great, fluttering clouds as they drop from the trees and become scattered by the wind across lawns and woodlots. Some of these seeds will germinate immediately while others may lay dormant in the soil until the following year. Many of these seeds will also be eaten by birds and squirrels. But these seeds and their seedlings are topics for a summer essay (and (great news!) summer is not that far away!)
What else is going on that could mean Spring is here? There’s some good news and some bad news, I am afraid. The bad news: deer ticks are active again! We have taken three off of our dog already and one off of our cat. The overwintering instars of the tick are up on the low vegetation and piles of sticks and leaves “questing” for passing warm blooded hosts. It is unlikely that the cold winter had any effect on the deer tick populations. Remember, if you get the tick off of you with 36 hours the chances of contracting Lyme disease stay very small, indeed.
Some more bad news involves some of the overwintering animals. Garter snakes, for example, are coming out of hibernation in spite of the lingering cold temperatures. Deborah and I found a small, dead garter snake alongside the Rock Furnace Trail last Sunday when we were out hiking. The snake was less than a foot long and quite thin, but didn’t have any external signs of injury. I think that had just crawled out of its hibernaculum and got caught in the developing cold of the day. I also found a very large fly cold to the point of immobility on the back bumper of my car! It must have woken up too soon, too. I don’t think that any of us will mourn the loss of a fly, though.
The good news includes the return of the killdeer to the area! We saw one over the weekend out in Allegheny Township and heard more when we walked in from the Penn State parking lot on Monday morning. The killdeer nest in the gravel on top of the flat roofed buildings here at Penn State New Kensington and act as “greeters” to anyone who dares to approach “their” buildings! We’ve also spotted more bluebirds on campus and there are so many robins that they have assumed their role as common birds! We are waiting for warblers, though!
Around my house the chipmunks are becoming very numerous (much to Izzy’s great delight!) and a group of red squirrels have begun to alternate with the army of gray squirrels at my sunflower feeders. I also saw my resident woodchuck dashing in and out of his burrow down in my woodlot, and spotted the pileated woodpecker making his feeding circuit between my black cherry trees. Yesterday afternoon I heard the male song sparrows start to sing, too. The stand of arbor vitae on the east side of the house is a favorite mating/nesting site for them! And, last night in response to a warm soaking rain the earthworms came up! (they had better dig back down into the soil, though, freezing temperatures are coming tonight!).
Ignore the snow. Spring is here!