Weed and Feed products will not kill poison ivy. This common lawn care product combines fertilizer, which promotes grass growth, and a selective herbicide intended to manage broadleaf weeds like dandelions and clover. Because poison ivy is a resilient, woody plant with a complex root structure, the chemicals and concentrations in these lawn treatments are inadequate for eradication.
Why Standard Weed and Feed Products Fall Short
Standard Weed and Feed products use selective herbicides, such as 2,4-D or dicamba, which target the growth mechanisms of shallow-rooted broadleaf plants without harming turfgrass. Poison ivy, however, is a woody vine or shrub and requires a more potent, specialized chemical approach. The herbicide concentration in Weed and Feed is too low to penetrate and destroy the entire plant, especially its deep root system. Applying these products only causes minor, temporary damage to the foliage, allowing the plant to quickly regrow.
The Structure of Poison Ivy
The inability of selective herbicides to kill poison ivy is due to the plant’s physical defenses and extensive underground network. The leaves are covered in a tough, waxy outer layer, or cuticle, which acts as a barrier against topical chemicals. This layer prevents low-concentration sprays from being absorbed efficiently into the plant’s vascular system. Furthermore, the plant’s survival is ensured by its robust, deep rhizomes and woody rootstock. These underground structures store significant energy reserves, allowing the plant to rapidly sprout new growth. True eradication requires a chemical that can travel from the treated leaves all the way down to these deep roots.
Systemic Herbicides and Removal Techniques
Effective control of poison ivy requires systemic herbicides, which are designed to be absorbed by the leaves and translocated throughout the entire plant, including the roots. The most successful active ingredients are glyphosate and triclopyr, the latter often labeled as a brush killer. These chemicals must be applied when the plant is actively growing, typically from late spring through early summer, just before or during its flowering stage.
Targeted Application Methods
For smaller patches or vines growing near desirable plants, targeted application prevents damage to surrounding vegetation. You can paint the herbicide directly onto the leaves or use a wick applicator to minimize spray drift. For large or climbing vines, a cut-stump treatment is highly effective. The vine should be cut a few inches above the ground, and concentrated herbicide applied immediately to the fresh cut surface. This ensures the chemical travels directly into the root system.
Physical Removal
For a non-chemical alternative, physical removal, or “grubbing out,” is effective for young or small plants. This technique involves digging up the entire plant, including all the roots and rhizomes. Due to their extensive network, this can be a difficult task. Regardless of the method chosen, repeat applications or follow-up digging may be necessary over several seasons to manage new sprouts from surviving root fragments.
Protecting Yourself from Urushiol Exposure
All parts of the poison ivy plant, including the roots and dead material, contain urushiol, a highly allergenic oil. Contact with this oil causes an irritating rash, making personal protection necessary during any removal effort. Wear long sleeves, long pants, boots, and waterproof gloves to create a barrier between your skin and the plant.
After handling the plant, all tools, clothing, and surfaces that contacted urushiol must be thoroughly cleaned. The oil can remain active on objects for an extended period. Tools should be wiped down with rubbing alcohol or degreasing dish soap and water. Clothing must be washed separately in hot water with a heavy-duty detergent. Never burn poison ivy, as the urushiol oil can vaporize in the smoke and cause a severe allergic reaction if inhaled.