The genista broom moth, which during its life cycle exists as the sophora worm, is extant in San Bernardino County. Known by its scientific name, uresiphita reversalis, the genista broom is a moth in the family crambidae found in North America, where it has been recorded from Nova Scotia to Florida, west to California, north to Colorado, Nebraska and Iowa. It is also found in Mexico and Cuba, Bermuda, Puerto Rico and Jamaica.
The uresiphita reversalis has a wingspan from one inch to 1.27 inches. The forewings are light to medium brown with dark antemedial and postmedial lines and two dark discal spots. The hindwings are yellow or orange with brownish-gray shading at the apex. Adults are on wing year round in multiple generations per year in the southern part of the range.
The larvae feed on acacia, lonicera, baptisia (including baptista leucantha), genista (including genista monspessulana) and lupinusspecies (including lupinus arboreus and lupinus diffusus), sophora secundiflora, lagerstroemia indica, cytius scoparius and cytius striatus. The larvae have a brownish-green body and a black head with white dots. The species usually overwinters in the pupal stage, but may also overwinter as an adult.
The first known description of this moth was by Achille Guenée in 1854.
To some people with gardens, in particular those growing baptisia, which is also refereed to as false indigo, and sophora secundiflora, called the Texas mountain laurel, the genista broom moth is considered a pest. More accurately, it is actually the caterpillars that cause the damage. Like most moths, all the adults can do is feed on nectar since they do not have any chewing mouth parts as an adult.
This insect pest is native to the southwest United States but usually doesn’t make it up into colder climates. In recent years, there were reports of this insect causing feeding damage to baptisias along the East Coast. These moths may also feed on other members of the pea (fabaceae) family, including flowers like lupine, shrubs like caragana, genista and honeysuckle, and potentially trees like the Kentucky coffee tree and honey locust.
The adult moth lays eggs on the plants. Then the young larvae together in a web feed on the leaves inside the web until they grow a bit larger. They eventually move out and start feeding on other parts of the plant or move on to other plants. The larvae can grow to about one inch long, are a dark tan-orange with white hairs and black spots. Normally, they will have two generations per year, but in areas with a short growing season, they may only have one generation per year.
As pests, they are not likely kill a plant, just cause feeding damage to the leaves, which may cause them to turn black. However, if they are present prolifically, the caterpillars could damage young, newly established plants if they become defoliated a few years in a row.
Treatment of genista broom moth damage can be as easy as just trimming off the affected foliage, hopefully removing the caterpillars with the leaves. You can pick off others and squish them to provide pretty good control. If you catch the infestation early, you can use bacillus thuringiensis against the invaders. This is a bacteria that you spray on the plants. Once it is ingested by the caterpillars, it will kill them. It is effective for any type of caterpillar pest but normally doesn’t work well for more mature larvae.
From Wikipedia and https://extension.sdstate.