Bacillus thuringiensis subsp. galleriae strain SDS-502
Btg is a strain of the soil bacterium Bacillus thuringiensis that makes a protein, Cry8Da, toxic to scarab beetles. One strain, SDS-502, is sold by Phyllom BioProducts as beetleGONE!, a powder you spray on leaves against adult Japanese beetles, and grubGONE!, lawn granules for grubs. The leaf spray has decent evidence: in Kentucky trials it cut beetle feeding on roses and lindens for 3–14 days, and Minnesota Extension rates it moderately effective for one to two weeks. The grub granules have mixed results, from outright failure in Kentucky to 35–100% control in Purdue's summary. Although it is sold as a beetle Bt, it also kills caterpillars: feeding on sprayed milkweed killed 97–100% of young monarch caterpillars.
At a glance
- Mode
- Bacterial toxin; must be eaten
- Active
- 9.0% Btg strain SDS-502 (grubGONE! bag)
- Adults
- Feeding cut 3–14 days (Kentucky); 1–2 weeks (Minnesota)
- Grubs
- Failed in Kentucky; inconsistent (Minnesota); 35–100% (Purdue)
- Monarchs
- 97–100% of young larvae killed on sprayed milkweed
- Where to buy
- Online only (Minnesota Extension)
How it works
Like every Bt, it has to be eaten. The galleriae strain SDS-502 produces a crystal protein, Cry8Da, that is active against scarab beetles. Redmond and colleagues at the University of Kentucky tested it in the field and published in 2020. Sprays left on the leaves reduced adult Japanese beetle feeding on roses and lindens for 3–14 days after they had weathered, although most beetles held on treated leaves for 24 hours could still fly. The granules were a different story: they failed to control Japanese beetle grubs, whether applied early or late, under several turfgrasses at several sites. Purdue is more positive about grubs, citing control of 35–100% that varies with the grub species. Minnesota Extension calls recent university results inconsistent.
It is less selective than its beetle billing suggests. In the same Kentucky study, early-stage monarch caterpillars fed sprayed milkweed died at 97–100% in three trials, and fall armyworms fed treated grass gained less weight. Lady beetle larvae eating aphids from sprayed plants were unaffected. The authors conclude it should not be used in gardens with the larval food plants of monarchs or other non-pest butterflies and moths, especially species of conservation concern. The maker's claim that it spares butterflies is not supported by that work. It is still being sold: the maker's store listed both products at $79.99 in September 2026, and Minnesota Extension notes it is only available online.
Applying it
We could not retrieve the EPA-accepted labels for these products, so the figures below come from the maker's own quick-start guides and product pages (Phyllom BioProducts). Always follow the label on the bag.
beetleGONE!: 2–4 oz per gallon
Mix 2–4 oz of powder per gallon of water and spray the foliage where beetles are feeding. The maker says a 1 lb bag covers up to 8,000 sq ft.
Every 7–10 days
Do not let irrigation or rain wash it off the leaves. Mix only what you will use that day; use any extra within 7–10 days.
grubGONE!: 3 lb per 1,000 sq ft
Apply with a handheld or walk-behind spreader. The bag says 10 lb treats up to 5,000 sq ft, a lower rate than the maker's recommended 3 lb.
About ½ in of water
Rain or irrigation of about ½ in carries it to the root zone where grubs feed. The maker warns that overwatering may wash it away.
Cool and dry
The maker gives a shelf life of 2 years. Treated fruit and vegetables may be eaten the day of application, per the maker.
Pesticide sensitivity
It is a bacterium, not a contact poison, and it did not harm lady beetle larvae in Kentucky tests. It does kill young monarch caterpillars that eat treated milkweed. Check a product →
When to choose something else
The leaf spray is a reasonable short-term shield for roses. The grub granules are a gamble. Choose something else when:
- Milkweed or other butterfly food plants are nearby — it kills monarch caterpillars
- You need grubs controlled this season — the granules failed in Kentucky's field trials. The grub nematode Heterorhabditis bacteriophora is the other biological option extension services list
- You are trying to protect roses and the beetles keep coming — Minnesota Extension also lists neem oil for a few days' protection
- You were thinking of milky spore instead — Minnesota Extension says commercial products have shown no benefit in modern university trials; see milky spore
Where to buy
These are the products we could confirm on sale. They are not ranked. helpfulbugs takes no commission and does not sell either one.
- Phyllom beetleGONE! (Btg SDS-502, foliar powder)1 lb bag — up to 8,000 sq ftUS · HOME · ONLINE
- Phyllom grubGONE! G (9.0% Btg SDS-502 granules)10 lb bag — up to 5,000 sq ftUS · HOME · ONLINE
Bacillus thuringiensis subsp. galleriae strain SDS-502 by target
Rate and timing differ by what you are releasing it against. Each page below is the program for one pest.