As we enter the last week of April, many of our mid-spring landscape insect/mite pests continue to awaken & cause feeding symptoms on our ornamentals. This blog only talks over some of the typical mid-spring pests that plague our landscapes. Those discussed within include: Southern Red Spider Mites; Gypsy Moths; Evergreen Lace Bugs (e.g., rhododendron, azalea, & andromeda lace bugs); Nantucket Pine Tip Moth; Birch Leaf Miner; Hemlock Woolly Adelgid; Plant Leaf Galls (eriophyid mites).
Eastern Tent Caterpillar: The Landscape Harbinger of Spring
Throughout much of NJ during this week, the growing degree days (GDD) will be increasing consistently. By the end of the week, many areas will exceed 90 GDD, which means the eastern tent caterpillars will begin to hatch. Not all eggs will hatch at once since a staggered hatching period will potentially increase survival rates if the weather happens to cool again.
The photographs of the eastern tent caterpillar’s life cycle included in this blog were all taken during the spring of 2016 at the same site in Freehold, NJ. They are placed in chronological order covering a time span of 10 weeks from 1st egg hatch on 3/23/16 to late pupation on 6/2/16. In 2016, central NJ experienced a relatively warm early spring that enabled the speedy first hatching.
Landscape Pest Notes: Some Early Spring Insects/Mites
The accumulation of heat units (Growing Degree Days (GDD)) is increasing rapidly across many areas of New Jersey as we soon enter into the early weeks of April. If past histories or present-day monitoring indicate the need for interventions, then the best control windows for an increasing number of insect/mite pests are beginning to occur. The following is an incomplete listing of a handful of some of our early season landscape pests that may need to be scouted & possibly controlled. The insect/mite pests included here are: Hemlock Rust Mites; White Pine Weevils; Native Holly Leafminers; European Pine Sawflies; Honeylocust Spider Mites; White Pine Aphids; and Eastern Spruce Gall Adelgids.
Control of Nuisance Fungi in Landscape Mulch
Overview:
When used properly, mulches and composts can improve soils and provide many beneficial effects to plant health and vigor. Undesirable nuisance fungi, however, may also occur when different types of mulches or composts are used under certain conditions. Some of the more common examples of these nuisance fungi include the shotgun or artillery fungus (Sphaerobolus), slime molds (Physarum), stink horns (Mutinus), bird’s nest fungi (Crucibularium), toadstool mushrooms, and several plant pathogens. Although these nuisance fungi are mostly natural decomposers of organic matter and most of them are harmless, this blog discusses how the various nuisance fungi sometimes associated with mulches and composts can be controlled or minimized.
Accurately Timing Scouting by Using Plant Phenological Indicators
Challenges of Pest Controls
Accurately timing a control tactic against the most vulnerable stage of an insect’s development allows for the use of biorational pesticides as well as less use of traditional pesticides. Unfortunately, accurately timing controls is difficult because of the complex array of landscape plants and pests that can be present on any one site. IPM methods require knowledge of the pest’s life cycle stages and when the vulnerable stage occurs for each pest. It requires knowledge of what pesticides will suppress the pest as well as their relative toxicities. This extensive amount of information can become overwhelming, especially to the less experienced landscaper or arborist.
Some landscape managers often resign to the easy, yet environmentally unsound practice of using four or more preventative cover sprays of pesticides each year. Studies have shown that typically only 2% of a blanket spray actually hits a targeted pest, with the remaining 98% contaminating the surrounding environment. Is there another way that pesticides can be applied more intelligently?
IPM vs. PHC: Is There a Difference?
History
During the late 1950’s and early 1960’s, Integrated Pest Management (IPM) was an approach to field crop management that farmers increasingly began to practice in the United States. It took barely a decade for farm agriculture to fully realize the problems associated with the over-reliance on pesticides when controlling pests. The classic example of the overuse of the chlorinated hydrocarbon (DDT) immediately comes to mind. Despite the astonishing success that synthetic pesticides usually have at killing pests, some have failed with disastrous results. This especially has occurred when the same material was used repeatedly over extended periods of time. For this reason, the IPM approach became necessary for US farmers managing extensive row crops. Approximately 20-25 years after farmers began implementing IPM methods, the landscaping or “green industry” started to gradually incorporate IPM methods into their service programs.