We found some spruces with new female
Posted: Wed Jul 09, 2025 6:17 am
In late May, a friend and I were out for a stroll and happened to notice some Sitka spruce cones. Spruces, like most conifers, have both male and female sex organs on the same tree. We remembered reading that the female cones are usually borne near the top of a tree, while male cones are produced on lateral branches below that. That is not a firm rule, however.
cones down at our eye-level and some with old cones just a few feet above the ground. There were two big spruces with exuberant crops of new male cones reaching as far up as we could see, covering every visible branch (except one at the bottom with an old female cone). Those male cones were loaded with pollen that shook loose when the wind stirred country email list the branch. Both of those trees had little or no new needle growth at the tips of the branches.
We then began to look more closely at the branch tips, where new growth (called “spruce tips”) and cones commonly are produced. New growth usually appears at the very end of the branch, sometimes with one or two (or three or even five) sub-terminal bunches of new needles. But sometimes at least one of those sites was occupied by a male cone. We observe that new growth and cones are usually best developed on the best-lit sides of a tree, suggesting that the resources for producing those structures are most available there. But what determines the allocation of resources among the cones and new growth? And what regulates the location of the cones? Plant hormones are probably activated in different ways in different places. But what governs that activity?
Mary F. Willson is a retired professor of ecology.“On The Trails” appears every Wednesday in the Juneau Empire.
cones down at our eye-level and some with old cones just a few feet above the ground. There were two big spruces with exuberant crops of new male cones reaching as far up as we could see, covering every visible branch (except one at the bottom with an old female cone). Those male cones were loaded with pollen that shook loose when the wind stirred country email list the branch. Both of those trees had little or no new needle growth at the tips of the branches.
We then began to look more closely at the branch tips, where new growth (called “spruce tips”) and cones commonly are produced. New growth usually appears at the very end of the branch, sometimes with one or two (or three or even five) sub-terminal bunches of new needles. But sometimes at least one of those sites was occupied by a male cone. We observe that new growth and cones are usually best developed on the best-lit sides of a tree, suggesting that the resources for producing those structures are most available there. But what determines the allocation of resources among the cones and new growth? And what regulates the location of the cones? Plant hormones are probably activated in different ways in different places. But what governs that activity?
Mary F. Willson is a retired professor of ecology.“On The Trails” appears every Wednesday in the Juneau Empire.