Gardening Tips: January 9, 2013
First of all, I would like to wish all of you a very Happy New Year. I hope that 2013 will bring you good health, happiness and the opportunities to share these joys with others.
The title of this week’s column literally means “naked seeds” from the Greek words “gymnos” (naked) and “sperm” (seed). The ancient Greeks invented gymnasiums where men could box, wrestle and compete in other sporting events and these activities were carried on in the nude. I guess I am glad that this custom is no longer practiced today considering the mores of modern society.
Gymnosperms comprise a large group of plants that are considered to be more primitive than angiosperms (covered seeds) due to the fact that their seeds are borne without any protective covering. Angiosperms are also called flowering plants and their seeds are protected by an ovary of some sort.
Most of the gymnosperms we are familiar with such as pines, fir, hemlock and spruce do not produce flowers per say but instead bear their seeds in cones that are borne near the ends of mature branches. Not all gymnosperms are needle bearing, nor are they all evergreen. Ginkgo trees are also gymnosperms and they drop their leaves each fall, as do cypress and a few other species not commonly found in our climate. Thus, all evergreens and conifers, which are also called softwoods to the lumber industry, are gymnosperms but not all of them bear needles.
Evergreens vs. deciduous
Last week I mentioned that many evergreens are hardier than deciduous trees despite many of them having green tissue exposed to winter weather. This is partially due to the fact that they produce a thick, waxy, cuticle that resists desiccation, sort of a built in antidessicant. Like some animals, cold temperature also slows their metabolism substantially but even pine trees will droop their needles noticeably when the temperature gets below zero.
Most people are familiar with the seed bearing cones of many trees that are characteristic of that species, but few notice the smaller, less conspicuous cones, which shed the pollen. Do you ever wonder where all the yellow colored pollen that covers your car comes from each spring? If you look closely you will see little cone like structures that resemble Rice Crispies to me. They only last a few weeks but the woodier cones are much more persistent. Typically, an evergreen cone takes two years to mature after being pollinated in the spring.
Pinecones appear tightly closed until the seed within them is mature and then they open up exposing the naked seeds to the elements. Some conifers require extreme heat from a forest fire to open the cones; a fact that confounded park managers for many years. No fire means no reproduction for several important conifer species. These days I routinely see controlled burns in places such as Florida in order to allow the pines to reproduce.
Conifer seeds are highly nutritious and provide winter food for many species of wildlife. Occasionally you may encounter a huge pile of spruce cones at the base of a tree that have been “shucked” by an animal such as a red squirrel, which seem to relish this food that must taste like turpentine. I think that is one reason why red squirrels are rarely hunted or eaten by us humans. I guess if we were hungry enough, during this season of cold, snow and ice we might find them quite satisfactory.