No known vector.

Because seeds are very small and could easily be transported on gear or clothing, samples should be collected carefully and double-bagged, and all gear and clothing should be cleaned to prevent introduction of weed seeds to new fields by surveyors.

Roots are bright orange below soil surface. Stems and leaves are conspicuously hairy. The dust-like seeds are covered with indentations.

Stunted crop plants with smaller leaf area, shorter leaf petioles, and increased shoot/root ratios.

The best time to survey is likely 12 to 14 weeks after warm-season crops are planted, when flowers and mature shoots are most likely to be visible. Seeds can germinate whenever soil conditions are warm and moist and host plants are available. Shoots are first produced 7 to 8 weeks after germination, and flowers are produced 9 to 10 weeks after germination. Emergence can, however, take three months after germination.

Surveys should target fields of suitable hosts or fallow fields that are growing in well-drained soils such as sand and sandy-loams. In Africa, A. vogelii infestations are typically on annual cropping and in semi-arid areas with a 4 to 6 month growing season below a mile in altitude. Weather preference estimates (CABI, 2023): - Mean annual rainfall: 20 to 40 inches - Mean annual temperature: 66 to 78ºF - Mean maximum temperature of hottest month: 84 to 100ºF - Mean minimum temperature of coldest month: 42 to 60ºF - Absolute minimum temperature: 26 to 32ºF

Samples should be collected carefully and double-bagged. Clean all gear and clothing to prevent spreading seeds to new fields.

The Federal Noxious Weeds Disseminules of the United States provides keys and fact sheets that can help identify seeds of Federal Noxious Weeds, including Alectra spp. (Scher et al., 2015). It does not, however, show seeds of A. vogelii specifically.

This weed can be confused for other Striga species and symptoms on host plants are similar to nutrient deficiencies.

Send to an approved botanist for identification.