Identification and Damage

• Beetle grubs: attack roots, turning lawns yellow.
• Otiorhynchus grubs: gnaw roots and leaves.
• Difference: humped = yellowish body, large head; ketone = white, small head, bulky back.

Natural Prevention

• Remove grubs by hand when digging.
• Encourage predators (birds, hedgehogs, moles).
• Maintain a robust lawn:
• Mow less frequently (8-10 cm in summer).
• Sow clover, fescue, and bluegrass.
• Water evenly but deeply.
• Avoid excess nitrogen.

Control: Nematode Control

• Use Heterorhabditis bacteriophora.
• Dosage: 5 μM of nematodes/10 m2, up to 500 μM/1000 m2.
• Dissolve in water and water the soil.

Application Periods

• Otiorhynchus: fall + spring.
• Chafer: winter, repeat 3 consecutive years.

Optimal Conditions

• Soil between 12°C and 25°C.
• Water before and after treatment. Keep moist for 1 month.
• Apply in the morning, evening, or on a cloudy day.

Advantages of Nematodes

• Safe for beneficial insects, crops, animals, and humans.
• Sustainable action thanks to its multiplication in larvae.

An effective, ecological, and sustainable method for protecting gardens and orchards against white grubs.