Garden Center Hours: Mon-Sat 9am - 5:30pm • Sun 10am - 5:30pm

Caterpillar Alert!

tussock moth

I have had several customers bring me Tussock Moth Caterpillars they found munching on their oak tree leaves.

The creamy white hairs on the caterpillar are long and bristle-like and spread out in tufts down the sides. Two long, sharp black pencil like hairs protrude near the front and rear and these hairs are connected to poison glands, which excrete venom on contact. Contact with the venom may result in itchy irritation.

You can spray your tree with Hi Yield Thuricide Concentrate or Natural Guard Spinosad Hose-end. Both of these products are organic and safe to use on all plants. Thuricide reacts with the cells of the stomach lining of the target pest causing them to not be able to feed within hours of ingesting. Spinosad is a contact kill, but still safe and organic for all plants.

(photo via


Reader Interactions


  1. Terry says

    Will Thuricide or Spinosad be harmful to birds? So many warblers passing through I wouldn’t want to cause injury or death.

    • james gill says

      Copied from National Pesticide Information Center
      Can spinosad affect birds, fish, or other wildlife?
      Spinosad is practically non-toxic to moderately toxic to fish depending on the species. It is slightly to moderately toxic to aquatic invertebrates. However, spinosad is very highly toxic to eastern oysters. Spinosad is practically non-toxic to slightly toxic to birds, based on studies with bobwhite quail and mallard ducks. It is moderately toxic to earthworms. Spinosad is very highly toxic to bees. However, evidence suggests that spinosad has little or no effect on honey bees and other beneficial insects after sprays have dried.

    • james says

      Spinosad is an organic with relatively low toxicity and breaks down quickly, but as with most pesticides you should remove their toys and dishes from the area to be treated, and let the treated area dry before letting the dogs out. That said, Confortis Flea Control for dogs and cats is Spinosad in a chewable tablet. Not to say it is good for dogs, but apparently they can tolerate it to the degree prescribed to kill fleas.

Leave a Reply

Your email address will not be published. Required fields are marked *

Better than your average email.

The Gill Garden News

Sign up for the Gill Garden News, our weekly e-newsletter! Each Thursday at 6pm, you’ll receive the Garden News direct to your inbox, packed with a weekly gardening blog, garden tips, weekly in-store specials, updates about events, and lots more.