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Huisache (Acacia farnesiana [L.] Willd.), a pest tree species on rangelands throughout south Texas, resists control via herbicide, fire, or mechanical methods through vigorous resprouting and prolific seed production. Until now, however, it has been unknown when huisache seedlings develop the ability to resprout. We determined the age at which huisache seedlings� cotyledon latent meristems are buried below the soil surface and plants attain resprouting ability. First, we grew 120 seedlings in the glasshouse and examined 10 every other month for 24 months to measure height of cotyledon latent meristem above (or below) soil level. Second, we grew 240 seedlings in the glasshouse, and cut 10 every month at the soil surface to determine resprouting ability. Seedling resprouting began at 6 months and increased to over 50% at 20 months.� Seedling cotyledon latent meristem height had a quadratic relationship with time, with average cotyledon latent meristem height at or below soil level at 22 months of age.� Seedling cotyledon latent meristems began to become buried at 7 months, with over 50% becoming buried at 21 months of age. We suggest that attempts at controlling huisache through top-removal methods might result in over 50% of plants resprouting when as young as 20 months of age.