Identify pinion needle scaleWe are going to look at this insect because eggs are being laid. Two year old needles are being cast off. This is a sign of infestation. There is also sparse, open foliage. This tends to be a chronic infestation. The insect is the pinion needle scale. You can see tiny, bean shaped bumps on the 2 year old needles. The insects move to last years new growth and feast on the sap of the needle all summer. You can see egg masses and web on the trunk of the tree. The insects thrive anywhere they are protected. You can use a garden hose and wash off the webbing and the eggs. Make sure you clean up to prevent reinfestation. You can reduce the population without using chemicals. The insects go from tree to tree by wind or the insects walking to other trees. The eggs are laid from late February to late April. You need to monitor your trees for signs of the insects. You can use a foliage systemic insecticide. These are most effective right after the eggs hatch. Dorman oil is not the ideal way to control the insects. Soil applied systemic pesticide reportedly shows good control. This is a good time of the year to do control just by washing the eggs off the trees.