How to Prevent Insect & Disease Problems on Trees & Shrubs
“An ounce of prevention is worth a pound of cure”
– Benjamin Franklin
Getting an early start on dealing with insect and disease issues can make all the difference between a beautiful, healthy landscape and one that’s plagued by problems all season. By focusing on prevention, rather than reacting to disease and pest infestation when it happens, you save money that may be spent on unnecessary pesticides and get to enjoy a more attractive environment.
Prevention involves a number of steps, including proper monitoring, plant care, and treatment. It often follows an approach called Integrated Pest Management (IPM).
This streamlined, ecological approach to pest management provides more effective results with less need for harmful chemicals. Ultimately, results are more successful and the process is safer for people, pets, and the environment.
How Does IPM Work?
IPM uses lots of tools in the pest- and disease-fighting toolbox. These include regular monitoring of pest populations for fast action, the use of proper plant care practices, planting pest-resistant varieties, and treating when needed. The ultimate goal is to manage for long-term prevention. If pest populations are kept down or eliminated, they will cause fewer problems in the yard or garden.
Let’s take a closer look at the essentials of IPM that you can apply them on your own property.
Regular monitoring of plants for pests allows for early detection when populations are low and easy to eradicate. The key is stopping them before their numbers get out of control.
Take, for example, monitoring for mountain pine beetle. The best time to check for these pests is in winter. Check for “pitch tubes” on the trunks of your trees. If you see pitch tubes, cut a piece of bark off and see if the wood under the bark is discolored bluish-gray. If so, the tree(s) need to be removed. If you regularly check your pine trees in winter and remove infested trees, the beetles won’t have a chance to spread and damage other trees. It’s all a matter of well-timed monitoring and action.
Use Good Plant Care Practices
There’s a lot you can do to keep pests and diseases at bay just by using good plant care practices.
For example, something as simple as keeping plants and beds clean and well-tended can help control numerous insect pests. Rotating annual crops from one part of the garden to another from year to year can reduce problems with certain pests, and removing old leaf litter from the base of plants can dissuade other problematic insects. Timed planting, to avoid windows of emergence for specific pests, can also reduce or eliminate damage.
Water plants well throughout the year (drought-stressed plants are more susceptible to damage). If necessary, amend the soil before planting and apply organic matter regularly. Use a thick layer of organic mulch to suppress weeds and retain moisture. And provide extra care to newly-planted trees and shrubs, as well as ones that have suffered damage.
Plant Pest-resistant Varieties – If there is a popular plant that is prone to specific pest problems, it’s likely that a resistant variety has been bred for it. Choosing varieties that are generally more vigorous and robust can also help with pest resistance.
Right Plant in the Right Place – Each plant has a preference for soil type, moisture, sunlight, temperature, space and more. Planting the wrong plant in the wrong location or conditions will only stress it to the point that it becomes a target for insect pests and diseases.
Encourage Plant Diversity – When pests like Mountain Pine Beetle become prevalent, they can wipe out entire areas of trees. It’s important to have several different kinds of trees, plants, and shrubs, not only to ensure that you’ll have something left if one of those pests attacks, but to improve the overall look and health of your landscape.
>> For some good options that grow well in our part of Colorado, see our articles on the best spring-blooming trees, great conifers, and trees for small spaces.
Treat When Needed
Before applying treatments (such as insecticides), consider whether there are already “biological controls” in place. The most popular biological controls for homeowners are beneficial insects. These are garden-friendly insects, such as ladybugs, lacewings, praying mantids, and parasitic wasps, which can consume insect pests in huge numbers. If you’re seeing large numbers of these, you may want to hold off on using pesticides to give the beneficial insects a chance to do their job.
If things get out of balance and more drastic measures are needed, give us a call. We’ll inspect your property to diagnose the problem and recommend the most effective and least toxic treatment options.
But keep in mind that close monitoring and treatment before problems emerge will be most effective.