Tree Spraying - Ask Extension
I live in South east centennial- arap county- bordering douglas county. Should I spray ash to defend against ash borer; spray pines to defend agains...
Knowledgebase
Tree Spraying #171905
Asked March 27, 2014, 10:48 PM EDT
I live in South east centennial- arap county- bordering douglas county. Should I spray ash to defend against ash borer; spray pines to defend against pine beetle? I'm getting mixed info from neighbors v companies that sell the spray service. Also does spraying for aphids when no aphids are present do anything for trees?
Arapahoe County Colorado
Expert Response
There is no need to treat ash trees in Arapahoe County for Emerald Ash Borer at this time. EAB has been found only in Boulder to date. However, if you know your ash trees are stressed or struggling, it may help to spray preventively in late April for Lilac-Ash Borer.
Mountain pine beetle (MPB) is generally more of a problem in foothills/mountain areas on ponderosa and lodgepole pines. While MPB has attacked and killed several Ponderosa, Austrian and Scotch pines in urban area landscapes, most of those were in foothills/urban interface areas. There is lower need to spray preventively for MPB in your area (unless you or a neighbor has brought in infested firewood from mountain/foothills areas and stacked it near landscape pines).
If you know that your pines are stressed/struggling, not growing much and neighbors have lost pines to IPS beetle injury, preventive sprays in April may be worthwhile.
A tree treated with preventive systemic insecticide will usually have fewer aphids later.
Aphids can often be whisked off a tree with strong streams of water.
See also:
http://www.ext.colostate.edu/pubs/insect/05558.html http://www.ext.colostate.edu/pubs/insect/05528.html http://www.ext.colostate.edu/pubs/insect/05511.html
Mountain pine beetle (MPB) is generally more of a problem in foothills/mountain areas on ponderosa and lodgepole pines. While MPB has attacked and killed several Ponderosa, Austrian and Scotch pines in urban area landscapes, most of those were in foothills/urban interface areas. There is lower need to spray preventively for MPB in your area (unless you or a neighbor has brought in infested firewood from mountain/foothills areas and stacked it near landscape pines).
If you know that your pines are stressed/struggling, not growing much and neighbors have lost pines to IPS beetle injury, preventive sprays in April may be worthwhile.
A tree treated with preventive systemic insecticide will usually have fewer aphids later.
Aphids can often be whisked off a tree with strong streams of water.
See also:
http://www.ext.colostate.edu/pubs/insect/05558.html http://www.ext.colostate.edu/pubs/insect/05528.html http://www.ext.colostate.edu/pubs/insect/05511.html
