One of the great (and scary) things in nature is that every living thing on the planet has a natural enemy – or two. Even more amazing is that many natural enemies are specific to their targeted prey. In the world of bio-rational controls, this is especially remarkable. One of the great benefits of bio-rational controls in the garden or crop is that they target one family or species of pest and leave all the others – particularly the beneficial insects – alone.
Milky Spore (Paenibacillus popilliae, formerly Bacillus popilliae) falls into the category of bio-rational controls because of its target specificity. While there is no evidence that it will help to control other white, C-shaped grubs, it is a powerhouse treatment for control of the grub (larval stage) of the Japanese beetle. Milky Spore ticks all the safety boxes – it will not harm humans or other mammals, reptiles, aquatic life, or plant material. Click here for more information on the main ingredient in Milky Spore.
Milky Spore Can Inoculate the Soil for Up To 20 Years
Many controls for pest insects require
repeated applications with no end to it in sight. Milky Spore, however, has the
added benefit of inoculating the soil after several applications. What this means is that the soil will carry
enough of the bacillus that any grubs that hatch in the area will not survive.
Depending upon your climate, fully inoculating
the soil can take between 1 and 5 years.
- In warm climates inoculation requires 1 – 3 annual applications.
- In colder climates inoculation requires 3 – 5 annual applications.
Milky Spore begins working as soon as
applied so long as grubs are feeding. This means spring and autumn applications
of Milky Spore are most effective because the grubs are most active at that
time. Don’t forget that beneficial nematodes are great for seasonal control of
the Japanese Beetle. They are effective on a broad range of in-soil pest
insects and they will help to more effectively distribute the powder form of
Milky Spore.
The cause of death from P. popilliae is not fully understood.
The most likely cause is from starvation as the bacterial cells grow in the grub’s
hemolymph - the blood-like fluid in invertebrates. The already milky looking
grubs become even milkier looking and fail to mature.
Damage from Japanese Beetles |
Milky Spore is available in powder and a
new granular formulation. The granular product is applied using a hand spreader
or a drop spreader. The powder formulation can be applied with a dispenser tube
or for small areas, by the teaspoonful spaced in a checkerboard pattern every 4
feet.
Community use of Milky Spore will help
to most effectively reduce the population of the Japanese beetle in your area.
Remember, the adult beetles are not affected by the Milky Spore and by their
nature are highly mobile – they will be moving into your area throughout the
summer months. The more of your neighbors who inoculate their soil, the better
the control will be.
Posted by Deb N.