Keep Winter Bugs at Bay with Dormant Oil
November 4, 2014
We know you’re busy with the approaching holidays and the last thing you want to think about is tree care. However, winter is an important time for pruning and key pest control treatments. If you want to control insects like scale and other spring pests on your trees, hollies and other shrubs, now’s the time to get on our winter schedule. It’s important to apply dormant oil at just the right time, which usually falls around the end of December through early March.
What is dormant oil?
Dormant oils are made from mineral oil, derived from very refined petroleum oil. Impurities are removed that may be harmful to plants. It is then combined with an emulsifier so it can be mixed with water and applied to plants. Our dormant oil is approved by the Organic Materials Review Institute (OMRI). It is safe to use around birds and animals, and does not harm reptiles. However, be sure ponds with fish are covered. Because of the improved refinement in products used these days, the term “Horticultural Oil” is more commonly used to describe these treatments.
How does dormant oil benefit your trees?
Dormant oil or horticultural oil, protects your trees by suffocating winter pests that survive through winter in your tree’s cracks and fissures. These pests include aphids, leafhoppers, leafrollers, mealybugs, mites, scale and tent caterpillars. Shrubs and trees such as Hollies, Red Oak, Live Oak, Pecan or Maples are susceptible to scale. Dormant oil applied at the right time can significantly decrease or prevent these pests from damaging your trees. Dormant oil is also great at warding off many fungal diseases such as black spot on roses.
Why do we wait until winter to apply dormant oil?
Winter is the best time to apply dormant oil treatments. It gives us the best chance at knocking out the particular pests listed above before a big infestation occurs. Also, this is the time of year it will be least likely to harm beneficial insects. It’s best to apply dormant oil when temperatures are still cool so that new, actively, growing foliage emerging in spring isn’t accidentally damaged. We need to apply the oils when the insects are active but before your trees and shrubs have “bud break" - i.e., before spring flowers or leaves start to emerge.
Applying these horticultural oils in winter can save you from having to use a stronger pesticide to control an infestation come spring or summer. Prevention is the best medicine when it comes to preserving your valuable trees. Before you get too caught up in the whirlwind of the holidays, give us a call and schedule this important tree care!