May beetle, also known as May bug or June bug, refers to several species of beetles belonging to the genus Phyllophaga. They are commonly encountered pests in gardens, lawns, and agricultural fields. Here’s an overview of their symptoms, recommendations, causes, and preventive measures:

Symptoms:

1. Root Feeding Damage:
   • May beetle larvae, known as white grubs, feed on the roots of grasses, ornamental plants, and crops.
   • Symptoms of root feeding include wilting, yellowing, or browning of foliage, stunted growth, and patches of dead or dying grass in lawns.
2. Turf Damage:
   • In turfgrass areas, heavy infestations of May beetle larvae can cause significant damage, resulting in thinning or bare patches of grass and weakened turf.
   • Infested lawns may show signs of irregular or localized wilting, poor vigor, and increased susceptibility to drought stress.
3. Surface Feeding Damage:
   • Adult May beetles may also feed on the foliage of trees, shrubs, and garden plants.
   • Leaf damage typically consists of irregular holes or notches along leaf margins, particularly on deciduous trees and woody ornamentals.

Recommendations for Management:

1. Cultural Practices:
   • Maintain healthy plants and turf by providing proper irrigation, fertilization, and soil management practices.
   • Avoid overwatering and excessive nitrogen fertilization, as these can create conditions favorable for May beetle infestations.
2. Biological Control:
   • Introduce natural enemies of May beetles, such as parasitic wasps, predatory beetles, and nematodes, to help suppress larval populations.
   • Encourage biodiversity in gardens and landscapes to support populations of beneficial insects.
3. Chemical Control:
   • Apply insecticides labeled for white grub control if May beetle larval populations reach damaging levels and other control measures are ineffective.
   • Use insecticides judiciously and follow label instructions to minimize impacts on non-target organisms and the environment.

Causes:

1. Life Cycle:
   • May beetles have a one-year life cycle, with adults emerging from the soil in spring or early summer to mate and lay eggs.
   • Eggs are laid in soil, and larvae hatch and feed on plant roots and organic matter in the soil.
   • Larvae go through several instars (growth stages) before pupating in the soil.
   • Adult beetles emerge from pupae in the soil, completing the life cycle.
2. Environmental Factors:
   • Environmental conditions, such as soil moisture, temperature, and organic matter content, influence the development and abundance of May beetle populations.
   • Mild winters and warm, moist springs can favor May beetle survival and reproduction, leading to increased pest pressure in affected areas.

Preventive Measures:

1. Soil Management:
   • Improve soil drainage and aeration to discourage May beetle egg-laying and larval development.
   • Reduce thatch buildup in lawns and turfgrass to minimize habitat for May beetle larvae.
2. Crop Rotation:
   • Rotate susceptible crops in vegetable gardens and agricultural fields to reduce the buildup of May beetle populations in the soil.
   • Plant less susceptible crops in areas with a history of May beetle infestations.
3. Monitoring:
   • Monitor plants, especially turfgrass and young trees, for signs of May beetle damage, such as wilting, yellowing, or defoliation.
   • Conduct soil sampling to assess May beetle larval populations and identify areas at risk of infestation.
4. Early Intervention:
   • Implement control measures, such as biological or chemical treatments, early in the season when May beetle populations are still small and localized.
   • Regular monitoring and prompt action can help prevent widespread damage and reduce the need for more aggressive control measures later in the season.

By implementing these preventive measures and adopting an integrated pest management approach that combines cultural, biological, and chemical control tactics, growers can effectively manage May beetle infestations and minimize their impact on plants and landscapes. Regular monitoring and proactive management are key to preventing severe damage and maintaining healthy plant growth.