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April sunshine brings May ... budworms? That is what we have to look forward to again this summer — the spruce budworm dangling from our spruce trees, dropping onto whatever happens to lie beneath.

This isn’t a science fiction movie — they are native to Alaska.

What makes it science fiction are the sheer numbers causing severe damage in Fairbanks and North Pole areas.

The spruce budworm is a caterpillar, the larva of a 1/2-inch-long, brown-orange mottled moth.

Adults don’t cause damage.

It is the eating habit of their offspring, who start on buds and new needles in mid-May.

They are often first noticed in early to mid-June when they start dropping out of spruce trees on silken threads.

This is not normal behavior, but a result of over-competition for food supply.

Successful caterpillars pupate on branches, then emerge as moths in late June to early July.

Adults breed and then lay eggs, which start hatching in late July.

Rather than eat, the tiny caterpillar spins itself in webbing, usually under a bud scale, to hunker down for the winter. It saves its appetite for tender spring growth.

In such high numbers, these budworms are able to cause serious aesthetic damage by defoliation of branch tips and leaders.

This results in brown color and, more importantly, forked or split leaders.

Forked leaders in spruce can eventually lead to a hazard, as this is a weak point in the trunk as it grows taller.

The spruce budworm does not kill trees, although repeated defoliation adds stress that can push a tree over the edge, resulting in secondary pests and even death.

This is particularly true for spruce in urban settings, which are already subject to many stresses associated with living around humans.

The best thing a homeowner can do is offer good preventive care: Avoid disturbing the roots, soil compaction and trunk damage.

Avoid the application of herbicides and other chemicals on or near your landscape trees.

Take care of your trees as you would any other part of your garden.

Adequate water and fertilizer will boost a tree’s natural defenses and longevity.

Water weekly or biweekly throughout the summer. Put a garden hose on a slow trickle overnight, allowing the surrounding soil to become saturated.

Fertilize in the spring using a high phosphorus fertilizer or specialized tree fertilizer.

If you use granular fertilizer, dig small holes around the base of the tree starting 2 feet from the trunk and radiating out to 1 foot beyond the drip line.

Apply 1 pound per inch trunk diameter, distributing the fertilizer evenly in each hole.

Any tree that has been fertilized must also be watered generously to avoid root damage.

Pesticides are an option but there is no scientific research showing any products to be effective in Alaska at this time. There are systemic insecticides for trees that individuals are trying.

If you choose to use pesticides, be sure to read the label and follow directions or hire a professional applicator.

Cathy Turner is an integrated pest management technician for the Cooperative Extension Service-Tanana District, a part of the University of Alaska Fairbanks, working in cooperation with the U.S. Department of Agriculture. For questions, contact her at 907-474-5702 or fnclr@uaf.edu.