Ailanthus altissima or Ailanthus is commonly found in Solano County. Tree of Heaven is a hardy species imported from China during the mid-nineteenth century, established in the California foothills it is now found nation-wide. Prolific, its spreads readily by self-seeding and suckering, found on abandoned urban lots and along highways it flourishes under marginal conditions. Many consider it an invasive WEED!

Ailanthus has bi-pinnate compound leaves one to three feet long with 13-25 leaf-lets, the bark is silvery-gray with a pronounced diamond-like pattern on more established trees. Reddish-brown masses of seeds are visible during the summer. Ailanthus is fast growing with large diameter (0.75+ inch) stems growing ~three feet per year. The wood is weak with no known commercial value.

Cultural controls; difficult to eradicate once established. A combination of herbicide application and mechanical removal can be effective. Recently I pulled up 15 Ailanthus trees up to 5 inches in diameter with a farm tractor and heavy duty tow chain. Bottom line, stay vigilant, remove early and often.