Here in Washington, trees are such an important and present part of our life that we sometimes take them for granted. These sturdy giants that can outlive us and last for generations help frame our landscapes and improve our land value. But there are a lot of problems that trees face that can damage them or even affect their growth.
Of all the pests that can affect Washington trees, there is none more strange or unique than scale insects. Scale insects do not resemble insects in the traditional sense, which makes them extremely difficult to spot unless you know exactly what you are looking for.
Scale insects or tree scales are common on many trees, shrubs, groundcovers, and herbaceous plants where they feed on sap with their piercing mouthparts. Adults come in two forms; armored and soft scale and resemble barnacles or growths on the branches of trees.
Armored (Hard Scale) – Armored scales are protected by a hard shell that they hide under and feed. They do not produce honeydew like soft scales. They are also smaller, fatter, and rounder than soft scales.
Soft Scale – Soft scale insects do not have a hard shell but are instead protected by a waxy substance they secrete over themselves. They produce honeydew as a waste product. They are bigger than armored scales and look like round bumps.
Severe infestations can damage or kill twigs. Honeydew can ruin decks, patio furniture, and other landscape surfaces. Honeydew also attracts bees and ants that like to feed on it. A fungus called sooty mold fungus may grow on the honeydew giving the plants a dirty or sooty appearance.
The life cycle of scale insects is quite strange. Adult females emerge in the spring from their protective wax coating and lay their eggs. Over the next three weeks, the eggs will hatch, and “crawlers” will emerge. These larvae have legs, unlike their parents. They move about the tree searching for a place to settle down and feed. When they find a site, they like they use their mouth to suck the sap out of the tree. Over the next few months, the crawlers will lose their legs and turn into adults.
As we mentioned before, scale insects are not like other insects. Because of their protective coating and armor, traditional pesticides are not very effective against adults. Applications of dormant oil must be timed properly. The ideal time to eliminate tree scale is in the spring right after the new crawlers hatch. The crawlers are extremely vulnerable not only to pesticides but natural predators as well.
At Colonial Lawn and Garden, we know how important trees are to you and the environment. That’s why we don’t just offer an amazing lawn care program, but we also provide top-notch tree and shrub programs to keep your trees healthy and strong for generations to enjoy.
To get started and to beat the rush, call us today at (509) 966-1655 in Yakima or (509) 371-1655 for the Tri-Cities area. You can also request a free estimate here. Keep track of our monthly blog for the latest and greatest tips on irrigation, lawn care, tree care, pest control, and more. Follow us on Facebook and Twitter if you’d like to hear about our latest offerings and news.