The Red Pine Scale, Matsucoccus resinosae, is an invasive pest of red pine. This native of Asia was first introduced to New York around 1939, possibly arriving on horticultural plantings for a World Fair. The first report of an outbreak was from Connecticut in 1946. The small size of the scale makes it difficult to see. Large infestations are noted for red dying and dead needles and visible waxy secretions of the feeding scales. Infestations of the Red Pine Scale have greatly increased during the past decade.
Why is this pest problem increasing now, decades after introduction of the scale? Red pines were extensively planted in the 1900s to reforest areas that were damaged by fire, returned to the wild or to protect watersheds. Red pine was chosen it part because of its longevity and seeming resistance to insects. Red pine is not native to many of the localities where it was planted. Many of the stands are now mature and factors within the stand may leave them more vulnerable to insects. Changes in climate or weather related stress can increase vulnerability to insects. Genetic changes could have occurred in the Red Pine Scale that better adapt it to its new habitat. For whatever reason, stands of red pines across the northeast US are being increasingly killed by Red Pine Scale.
These stand deaths have forced forest managers to reevaluate their strategies. Many foresters are harvesting red pines, either after they are dead and dying or as part of a managed plan. Red pine replaces many of the native tree species that might be more sustainable.*
The crisis of a stand death demands a plan and a response. A public who has become accustomed to the recent character of these areas may be unaware of the historical ecology of the area and changes introduced by common management practices long ago. The activity of the Red Pine Scale is creating challenges and opportunities in ecosystem management.