The prickly pear cactus (Opuntia) is a succulent plant characterized by its flattened, jointed stem segments, or pads. While native to the Americas, the plant has spread globally and is considered an aggressive invasive species in many regions outside its native range. Prickly pear often forms dense, impenetrable thickets that pose significant problems for land management. These patches reduce land productivity, compete with desirable vegetation, and present a physical hazard to livestock, pets, and humans, which is the primary motivation for seeking effective removal methods.
Safety First: Handling the Spines
Prioritizing personal safety is essential before attempting any removal due to the plant’s dual defense system. Prickly pear features large, visible spines and tiny, barbed hairs called glochids. Glochids are particularly hazardous because they detach easily, possess microscopic barbs, and cause persistent skin irritation that is difficult to see and remove.
Workers should wear thick protective gear, including leather or specialized puncture-resistant gloves, long sleeves and pants, and sturdy, closed-toe footwear. If glochids penetrate the skin, do not rub the area, as this drives the barbs deeper. A common removal method involves gently pressing duct tape or packing tape over the affected area and quickly pulling it off to lift the tiny spines.
Mechanical Removal Methods
Mechanical removal is a non-chemical approach highly effective for clearing small, scattered infestations. This labor-intensive method involves physically digging up the entire plant, ensuring immediate eradication. Tools like a heavy-duty shovel, grubbing hoe, or specialized tongs are used to handle the prickly material and sever the plant from the soil.
The most critical step is extracting the entire root crown, the basal area where the pads meet the soil. If the crown is left intact, the plant can regrow rapidly, negating the effort. For larger, denser infestations, heavy machinery like a skid-loader equipped with a rock rake can be used to uproot the plants and minimize topsoil disturbance. Thoroughness is essential because every severed pad can re-root and establish a new plant. All detached pads must be carefully collected from the ground to prevent re-establishment. This technique is most successful during hot, dry conditions, which stresses any remaining root fragments.
Targeted Herbicide Application
For large or dense infestations where mechanical removal is impractical, targeted herbicide application provides an effective chemical control option. Successful treatment requires herbicides known to penetrate the cactus’s waxy cuticle and translocate throughout the plant. Effective active ingredients often include picloram, sometimes combined with fluroxypyr or triclopyr, which can achieve high mortality rates when applied correctly.
The application method is typically a targeted pad and stem spray, not a broad broadcast application. The herbicide solution, often mixed with a non-ionic surfactant (NIS) to aid penetration, must thoroughly wet all pads and stems without excessive runoff. It is beneficial to spray both sides of the pads for better absorption.
Timing is important for maximizing efficacy, being most effective during the plant’s active growing season or late summer and early fall when resources move toward the roots. Prickly pear is slow to die after chemical treatment; visible effects may take six to eight months, and full mortality can take a year or more. Users must always follow the herbicide label directions precisely, especially since powerful treatments like picloram are restricted-use pesticides requiring a certified applicator’s license.
Disposal and Preventing Re-Establishment
Proper disposal of removed prickly pear material is necessary to prevent severed pads from re-rooting and undoing the removal effort. The pads are highly resilient and can remain dormant before growing into a new cactus if left on the soil surface. Piling the material should be avoided, as the pads will root together and form an impenetrable mound.
One reliable disposal method is to allow the pads to desiccate completely by placing them on a tarp or concrete surface in the sun for several months until they are fully dried and shriveled. Alternatively, the material can be buried deep, ideally under 18 to 24 inches of soil, to prevent new growth. Burning is also an option where local regulations permit, but the cactus does not burn easily and often requires significant ancillary fuel.
Following removal, site monitoring is required for at least one to two seasons to treat emergent sprouts. Small seedlings that germinate from seeds or sprouts from missed root fragments should be removed manually when they are young. Regular maintenance ensures the area remains clear and prevents recurrence.