Question:
We live in Wisconsin and have noticed that the
conifers are especially laden with cones this year. Many other
years the trees have had cones mostly at the top. But this year
many of the trees are heavy with cones top to bottom, to the point
where the look brown rather than the regular rich green of fall.
The branches are bending with the weight of the cones. We are
wondering why so many? Is this part of a conifer's life cycle as
many of the trees aroun our property were planted at the same time?
Is this an indication of a harsh winter? Could you help us out? Thank you.
Replies:
The phenomenon is called "mast seeding" and is found in many tree species.
Causes are debated, but it is definitely not a predictor of the coming
winter weather. Mast seeding may be a response to favorable growing
conditions in the previous season(s), or a strategy that evolved to increase
reproductive success by sating seed predators in a given year, so that there
is better chance of some seeds surviving to grow. Here is a selection from
the abstract from a technical study on mast seeding, by Kelly and Sork,
from the Annual Review of Ecology and Systematics
"For many years biologists have debated whether mast seeding (the
synchronous intermittent production of large seed crops in perennial plants)
results from weather conditions or is an evolved plant reproductive
strategy. ..... We conclude that masting is often an adaptive reproductive
trait overlaid on the direct influence of weather."
In other words, these authors conclude both factors are responsible.
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