The larvae of hag moth possess a unique defense mechanism through urticating hairs that can cause skin irritation upon contact. These hairs release toxins mechanically as a defense against predators. When touched, these hairs can mildly affect human skin, leading to symptoms such as redness, itching, and a burning sensation. Generally, the effects are temporary, but severe cases may result in intense irritation and dermatitis. It is important for humans to handle hag moth with care to avoid these toxic effects.

Hag moth typically uses its sting to ward off threats or secure food, secreting venom that can cause a range of reactions depending on the species affected. Humans may experience painful swelling, while smaller mammals like cats or dogs could suffer more severe reactions. Birds, although generally less affected due to occasional encounters, may still feel discomfort if stung. Reactions can vary from mild irritation to severe, life-threatening conditions, particularly in those with allergies to the venom.

Hag moth's larval stage can cause allergies in humans through contact with its hairs, affecting a small number of people. The allergic reactions range from mild to severe and may include itching, rashes, or respiratory issues. Individuals with higher sensitivity could experience more serious consequences. Being cautious and avoiding contact with the larvae is advised to mitigate risk.

The larva of hag moth has urticating hairs that release toxins defensively, which can irritate human skin upon contact. The reaction may vary from redness and itching to severe dermatitis in sensitive individuals. These troubles occur due to accidental or uninformed handling of the hag moth, or when humans come into contact with them in their natural habitats.

To prevent issues with hag moth, educate the community about their appearance and habitats. Protective clothing can be worn when in areas known to host hag moth. Regular garden maintenance reduces the likelihood of encountering their larvae. Avoid touching or handling them directly, and educate children to do the same.

If contact with hag moth occurs, gently remove any hairs from the skin without using bare hands, perhaps using tape or a commercial lint roller. Wash the affected area with soap and water. Cool compresses may alleviate symptoms. Keeping the affected skin clean and avoiding scratching will help minimize further irritation. During recovery, it's important to keep the area from infection and stay alert for any signs of increasing irritation or spreading of symptoms, at which point seeking professional advice without delay is recommended.

Upon feeding, hag moth larvae cause significant destruction to leaves of host plants such as oak, hickory, apple, cherry, and ash. The larvae chew the plant tissues, leading to defoliation which can reduce photosynthesis, stunt growth, and potentially decrease the overall vigor and fruit production of the plants.