What Is Happening To The White Pines?
(Pinus strobus)

A white pine branch overloaded with stress cones.
photo by Gerry Hawkes - February 2001

When trees are under severe stress and are likely to die within a few years, it is not uncommon for these stressed trees to produce an overabundance of seed. This is a physiological response to stress that saps most of the remaining vigor of a tree, but under normal conditions greatly increases the probability that some of their progeny will survive.

During the 2000-2001 seed year, many species of trees observed in Vermont, New Hampshire and New York were overloaded with stress crops of seed. This follows many years of declining health and vigor. Accounts of similar, simultaneous stress crops of seeds have come from as far away as South Carolina.

You can see in the photo above that the ratio of needles to cones is very small. Needle density on many overloaded branches is only about 1/4 what it should be for good tree health.

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A comment from Joe Aliff in Rock Creek, West Virginia:

In your photo of the stress cones, the curl and the folded needles are clearly visible.  Your photo is one of the VERY best examples of white pine needles that do not completely open to form the natural swirl that makes the full circle. You may want to use this example to note the branch tip curl and the extended needles (paint brush effect) as opposed to the swirl.   Three bad signs on one branch. When I pick a tree that is going to die, (3 years or so ) the paint brush effect of the needles, as opposed to a full swirl, is one of the most prominent signs that I look for.

White pines are dying in increasing numbers.
photo by Gerry Hawkes - August 2000

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Contact Gerry Hawkes: ghawkes@eco-systems.org