If you woke up today and discovered that the leaves on some of your garden plants were half eaten…and felt like crying when you spotted skeletonized leaves on the roses…you have probably been infested with sawfly larvae, and you are not alone. Yes, it is early May and they hatched, exploding in numbers, and may be seen on many plants in your garden.
Two rose sawflies on the underside of a rose leaf.
There are many species of sawflies, three of which feed on rose foliage and these are the ones that I worry about the most. Like most species of sawflies, they are green and small (maybe one-half inch long) and look like inch worms. Since they feed on the underside of leaves that is where to look for them.
Fortunately, if you find the little critters early enough, control is possible and damage can be minimized. Also, remember to be vigilant through June when they finally stop feeding.
Several options exist for control of sawflies. One method is to simply pick them off by hand or use a stick or a stream of water to dislodge them. If you use using water spray early in the day so foliage dries by sunset which avoids favorable conditions for fungal development. Horticultural oil, insecticidal soap and neem are low-toxicity insecticides for young sawflies. But we never have the luck to find the young ones, so a conventional insecticide is the better choice. Common insectides that are readily available are Orthene, Sevin, malathion, and diazinon. It is most important to avoid spraying the rose flowers because most conventional insecticides are highly toxic to bees.
Digging RI 
I have a lot of bindweed coming up in my perennial garden these days, but I’ve noticed this week that it’s being eaten by something, rather rapidly. I didn’t know to look on the bottom of the leaves so I’ll try that. But so far it’s just the weed that’s being attacked, so that seems like a good arrangement for the time being, right?
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You certainly are lucky. I guess you should just let nature take its course.
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There is no better way to garden! Thanks.
Sent from my iPod
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Thanks for this info! I have seen little green inchworm looking things devouring my broccoli plants. I wonder if they’re sawfly larvae. I really should learn how to spot larvae – what to be vigilent about, what to leave alone.
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Remember, these ar NOT catipillars. And therefore, don’t try to get rid of them with bt. I have a huge problem with them on hibiscus. They don’t stop by the end of June as mentioned above. Hand picking more than once a day does make a dent in the damage.
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You are right about Bt but it should be noted that it’s use is specifically to lepidopteran caterpillars.
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Hi fell upon your interest in caterpillers & thought you may be interested in this site:-http://lepidoptera.butterflyhouse.com.au/faqs/ident.html
cheers
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Thanks, Michael. This is an interesting and useful site.I have used it many times in trying to find out “who” is in my garden.
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