Crossbow

Asked March 23, 2020, 1:30 PM EDT

Do the ingredients in Crossbow contaminate the soil, harm microorganisms & worms n the soil, or harm bees? How long after applying it should pets stay out of the area? If so, how do I kill weeds safely other than hand removal?

Clackamas County Oregon

1 Response

Sorry to hear about your weed problems.

I am a bee extension faculty, so I can comment on the effects of crossbow on honey bees. Like most herbicides, the herbicidal ingredients in Crossbow (2,4-D Ester and triclopyr ) are relatively non toxic to honey bees when used according to the instructions on the label. But there appears to be other environmental effects, which you can find on the label under a section titled 'Environmental Hazards'. It states: "this pesticide is toxic to fish and may be toxic to aquatic invertebrates." In order to avoid these negative effects the label states"do not apply directly to water, to areas where surface water is present or to intertidal areas below the mean water mark".

The National Pesticide Information Center is a great source of information for other potential negative effects. You can call them directly during business hours and a knowledgable person will pick up the phone and answer all your questions on crossbow or any other pesticide (call
1.800.858.7378, M-F - 8AM-12PM). They have a great website (http://npic.orst.edu/) with information sheets on the herbicide ingredients in crossbow:
http://www.npic.orst.edu/factsheets/triclogen.pdf
http://npic.orst.edu/factsheets/24Dgen.html

Finally, before reaching for a herbicide, its good to figure out what your weed problem is and work up from there. The Master Gardener Hotlines are a great place to start (although these have been temporarily suspended and will continue after the COVID-19 danger passes) :
https://extension.oregonstate.edu/program/all/mg/local-programs

You can get advice from Ask An Expert - send in a description (and photo) of your weed problem and help will be on its way. Good luck.