Considering the recent media coverage of bark beetle-battling tactics that range from playing music that aggravates the insects to feeding host trees pureed crab shells, the Colorado State Forest Service advises landowners to carefully consider the preventive treatment options available to protect their pines.
The jury is still out on the efficacy of many options for preventing bark beetle infestation, but some mountain pine beetle prevention products have been tested more extensively for safety and effectiveness.
The Colorado State Forest Service provides a product overview of some common available treatments intended to prevent healthy trees from being infested by mountain pine beetles. It is important to note that the treatments listed do not save trees already infested by mountain pine beetles.
MPB Treatment: Carbaryl, Permetherine, Bifenthrin
Brand/Common Name: Sevin®, Astro®, Onyx®
Type: Chemical –Insecticide, Spray
Pros: Up to 97 percent effective for protecting lodgepole pines; EPA-registered and extensively tested
Cons: Should not be used near riparian areas; best for use on select trees (as opposed to stand-level applications)
MPB Treatment: Dinotefuran, Imidacloprid, Emamectin Benzoate
Brand/Common Name: Safari®, Marathon®, Proclain®
Type: Chemical – Insecticide, Soil Treatment or Trunk Injection
Pros: Powerful insecticides
Cons: Not tested directly on MPB; may require multiple applications; may kill other insect species; not approved for use on some conifers
MPB Treatment: Verbenone
Brand/Common Name: Beetle Block®, Hercon®
Type: Chemical – Pheromone
Pros: Effective for large stands and individual trees; demonstrated success in lodgepole pines with low MPB populations
Cons: Poor success in lodgepole pines with high MPB populations
MPB Treatment: Microbial Sprays
Brand/Common Name: Nationwide Organics
Cons: Not tested on MPB; little product information; ingredients not disclosed
MPB Treatment: Colloidal Chitosan
Brand/Common Name: AgriHouse ODC™, YEA®
Type: Organic Disease Control (ODC)
Pros: Improves tree vigor and defense mechanisms (i.e., resin production) in some pine species; natural
Cons: Not tested directly for impacts on MPB; not tested in lodgepole or ponderosa pines; may require multiple applications
CSFS Forest Entomologist Sky Stephens says that landowners should consult with a CSFS forester prior to selecting or administering any mountain pine beetle treatment to determine which product best meets the individual’s management objectives. She also suggests that landowners follow all product label instructions and warnings, and recommends using licensed pesticide applicators to apply chemical products.
More information about protecting pine trees from mountain pine beetle infestation is available at local CSFS district offices. To read the full product overview, go to http://csfs.colostate.edu/pdfs/mpb-prevention-products.pdf.