Budworm larva, damage, and frass. Photo: Jeremy Slone
In the photo above you have several indications that a caterpillar pest is present, whether you can immediately find the pest or not. If a budworm is present on a plant, you will not only see the damage done to the bud and nearby leaves, but you will also see frass (insect waste) that resembles pepper in the area below the feeding. If the signs are there, a caterpillar is likely present on the plant as well. The same holds true for hornworms except that they may be feeding on larger leaves and not solely on the bud. Also, hornworm frass has a characteristic barrel shape and is often larger.
This was the first week this season that we have hit threshold and required treatment in the IPM fields. In one of our Eastern sites, as well as one of our Piedmont sites, we were slightly above threshold for hornworms. Although we did not reach threshold for budworms, treatment for hornworms will typically provide budworm control as well. The standard field at one of the same sites was treated the previous week with a noticeable effect on the insect populations within the field and we expect to see the same for the IPM field in the week following the treatment.
Timing chemical treatments to maximize efficiency is critical to reduce the number of necessary sprays. Budworms feed within the somewhat-protected and growing bud and any new growth after spraying is not only without protection, but provides a viable food source. When treating for budworms or hornworms it is important to ensure that you are getting effective coverage into the bud of the plant and on as much foliar material as possible. This helps ensure that pests come into contact with the chemical, as foliage that does not get good coverage will also provide a viable food source for pests.
We anticipate seeing more budworm and hornworm pressure in the Piedmont region of the state now that we are farther into the season and fields in the Eastern part of the state are now reaching threshold. We are still seeing thrips, as well as flea beetles, at most of the sites, but they do not warrant treatment at our observed population densities. Aside from the pests, we are also seeing quite a few beneficial insects and natural enemies. Using more selective insecticides to treat only the pests you have can help preserve such diversity and abundance. Insects such as stilt bugs, lady beetles, and “big eye” bugs are all predatory on pests of tobacco and small parasitic wasps often assist in reducing pressure from caterpillar pests.
Eastern 1
Scouting Report, Eastern 1 – Grower Standard Field
Insect observation
No. aphid infested plants
Flea beetles per plant
Percent tobacco budworm infested plants
Hornworms per plant
Percent cutworm damaged plants
Other insects
Treatment needed?
0 – No treatment
0.0 flea beetles/plant– No treatment
0% budworm infested plants – No treatment
0 – No treatment
0 – No treatment
Scouting Report, Eastern 1 – IPM Field
Insect observation
No. aphid infested plants
Flea beetles per plant
Percent tobacco budworm infested plants
Hornworms per plant
Percent cutworm damaged plants
Other insects
Treatment needed?
0 – No treatment
0.2 flea beetles/plant– No treatment
0% budworm infested plants – No treatment
.04 – No treatment
0 – No treatment
Eastern 2
Scouting Report, Eastern 2 – Grower Standard Field
Insect observation
No. aphid infested plants
Flea beetles per plant
Percent tobacco budworm infested plants
Hornworms per plant
Percent cutworm damaged plants
Other insects
Treatment needed?
0 – No treatment
0.04 flea beetles/plant– No treatment
0% budworm infested plants – No treatment
0 – No treatment
0 – No treatment
Scouting Report, Eastern 2 – IPM Field
Insect observation
No. aphid infested plants
Flea beetles per plant
Percent tobacco budworm infested plants
Hornworms per plant
Percent cutworm damaged plants
Other insects
Treatment needed?
0 – No treatment
0.29 flea beetles/plant– No treatment
1% budworm infested plants – No treatment
0.11 – Requires treatment
0 – No treatment
Eastern 3
Scouting Report, Eastern 3 – Grower Standard Field
