Are you doing your part to protect your landscaping investment and minimize the impact of summer invasive tree pests in Seattle? All it takes is a simple, 10-minute tree inspection by yourself or a Seattle tree pest services expert to protect the state’s green spaces. August is the ideal time to ID invasive insects, when the summer heat sends pests out into the open. What pests should you be on the lookout for?
The most common insect in the landscape are aphids. Most plants get attacked at one time or another by one of the many species of aphids that arrive every spring. But a lesser know and sometimes misidentified relative is the woolly aphid.
Much like other types of aphids, these plant juice-sucking insect pests are fairly small. However, woolly aphids, which are green or blue, also appear fuzzy due to the white, waxy material that covers their body. These pests generally use two hosts: one for overwintering and laying eggs in spring, and one for feeding in summer. There are many types of woolly aphids, but the two most common we see are the Hackberry woolly aphid and the Woolly apple aphid. The hackberry woolly aphid is typically found mostly on Hackberry trees and by the end of the summer, their sticky mess below a large hackberry is impossible to miss.
Another solution to pest management that has become more popular in recent years is the release of beneficial insects. These are essentially good guy insects that attack the eggs or larva of the harmful insects. In the natural, their population in a given area varies a lot depending on the sources of food they have.
Beneficial insects are a valuable asset to the ecosystem, besides preying on harmful pests, they are good pollinators too. An example of a beneficial insect is green lacewing. They have a wide array of insect targets including aphids, psyllids, and Tussock moth and other caterpillars. Beneficial insect releases can be incorporated into plant health care programs, especially as a multi-year plan to combat ongoing pest infestations. Incorporating beneficial insects to your landscape help restore a healthy and natural balance to the environment.
How can you tell if your trees have pests or diseases? These problems can be challenging to recognize due to the sheer number of possible issues, and the fact that they may occur far above your head where they are difficult to spot! For this reason, pest infestation and tree diseases often go overlooked for years, then appear to progress quickly because they have gone unnoticed. Fortunately, there are common signs of poor tree health that can help you identify these problems early so you can get help from a professional arborist before you lose valuable trees. Find out if your trees have pests or health problems now with this handy list.
The Asian citrus psyllid is garnering a lot of attention lately, largely because it spreads a serious disease called citrus greening disease or huanglonbing.
The insect itself is a fairly important pest on citrus. It is native to Southwest Asia and introduced to the United States in 1998 and in California in 2008. They are smaller, brownish insects that are fairly hard to spot until they begin to do damage. The adults lay eggs on citrus leaves and when the young hatch they feed on the leaves, exuding a sticky substance called honeydew. This sticky mess on a citrus plant is often the first noticeable problem. Leaves will turn a pale green, with twig dieback and lead to small, underdeveloped fruit if not controlled.
Phytophthora root rot is caused by a soil-borne organism. When first infected, the coast redwood’s foliage may wilt, yellow and dry out but remain on the tree. The leaf damage is because of the slow death of the redwood’s roots, which limit its ability to absorb adequate amounts of water. Eventually, the entire tree will turn brown and is unlikely to recover. If caught early enough, phytophthora root rot’s presence in the soil may be managed, or at least reduced, with the application of a fungicide containing potassium phosphate. But this is not always successful.
One measurement we use in helping to determine overall soil health is soil pH. This is a common concept and important to understand, but is only one of many measurements we use to determine overall soil health. A good soil health recommendation will take many factors into consideration, but soil pH is the starting point, as it helps us determine nutrient availability, the tightness of soils, and the ability of soil biology to thrive or not. The wrong pH may encourage fungal pathogens, while the proper soil pH range will encourage good soil microbes.
The pH scale runs from 0 to 14. Any pH reading below 7 is acidic and any pH above 7 is alkaline. A pH of 7 indicates a neutral soil. Most trees will grow in soils having a pH between 6.5 (slightly acid) and 7.2 (slightly alkaline). Ideally, maintaining a soil close to 6.8 is perfect for most trees. There are a few plants that prefer a soil pH below 6.0. These “acid-loving” plants include azaleas, rhododendrons, and blueberries. The soil pH for these plants can be lowered by incorporating elemental sulfur (S) into the soil. Since the soil acidifying response to elemental sulfur is slow, it should be applied and incorporated a year before planting.
Keeping a watchful eye on tree wellness is crucial to preventing damage from common tree diseases in the Seattle area. What symptoms should you be on the lookout for in your Seattle, Bellevue, Kirkland, Redmond, Kent, Edmonds, or Bothell property’s trees?
