Fairway pecking
As
you will have seen we have had some damage to certain fairways here at Harleyford.
The 15th is worst hit however we also have damage on the 9th, 11th 13th & 14th fairways. The principle issue is that grubs live just under the surface eating the root of the grass plant, this
can cause a yellowing or weakening of the turf in spring. The main problem we
have seen is bird pecking on the fairways, this is when birds start pecking
looking for the grubs to eat.
Quick facts
Common name: Chafer Grub, Garden Chafer
Scientific name: Phyllopertha Horticla
Area affected: Golf greens, tees, fairways.
Symptoms: Chunks
of turf pulled back by birds foxes or badgers
Activity: Grubs September to April Beetles May – June
What are they?
Chafer
grubs are soil dwelling larvae of the chafer beetle. Depending on the species
of the chafer they feed on decaying plant material or plant roots. Some species
do not cause damage to turf as they live in plant borders and compost heaps,
however there are several species that feed on turf roots and can cause
problems on the golf course. The main problem are there predators.
Symptoms
Some
species of chafer grub eat the roots of grasses and other plants. Evidence of
their activities can be seen in a number of ways:
- Damage to turf is most
obvious in spring when the grubs are reaching maturity
- Patches of the turf
may become yellowish
- Birds, particularly
of the crow family (e.g. Jays, Magpies, Rooks Jackdaws and Crows), and
badgers and foxes tear up turf in order to access the grubs to feed on
them
- Damaging
infestations can be highly localised and sporadic hitting different
fairways and tees around the course.
- Chafer grubs can be
found in the soil under the loose turf. They have stout white bodies
curved in a C shape, light brown heads, with three pairs of legs at the
head end.
- Other less
troublesome species of chafer grubs can also occur in turf and garden
borders, such as the cockchafer
- Similar root damage in turf areas can also be caused by leatherjackets. Birds and foxes will also try to find theses under the turf and cause damage.
Control
Chemical
control
There
are currently no chemical controls for garden chafer grubs or Leatherjackets in
the amenity and sports turf industry. The active ingredient (Chlorpyrifos)
used to kill leatherjackets was withdrawn overnight on the 31st August
2015. Merit turf (Imidacloprid) was taken off the market in October 2015 and
all stock has to be used by October 2016. Luckily we have one hectare in stock
of merit turf to use in May on the 15th and 16th
fairways. Additionally this is a very expensive treatment which can run into 5 figures to complete.
Non-chemical
control
- Repair damaged turf
by re-sowing with grass seed or laying turf in April when the chafer grubs
have moved deeper into the soil to pupate.
- Shooting and
trapping and using bangers to move the birds that are doing the damage
away, but there are so many this year it’s a never ending task.
- You can buy
pathogenic nematodes, usually Heterorhabditis bacteriophora,
which attack the larvae by infecting them with a fatal bacterial disease.
These microscopic animals can be watered into the Turf when the ground is
moist and soil temperature range between 12-20ºC (55-68ºF). This
biological control is available by mail order from our chemical
suppliers. The turf around the edge of affected areas should be targeted
to deal with larvae spreading out from infestation “hot
spots”. However, by the time areas of infestation become apparent,
the soil may be too cold for nematodes to be effective. As a preventive
measure, we are looking apply nematodes around September. Nematodes should
be applied no longer than 5 days after delivery, We may have to water in
before and after application to ensure the soil is sufficiently moist for
nematode activity and survival. Nemitodes are a little hit and miss, now nemitodes
are the only thing on the market to deal with this problem.
Another
angle we are going to try is trapping the male beetle, this is for two reasons
the first is to see when they are active to apply the merit turf that we have
in stock. The other is to reduce the population by trapping them.
The
Garden Chafer Trap is a simple but effective product that can allow more
accurate treatment timings against the larval stage of this destructive pest.
The
trap will catch adult beetles and give an early warning of chafer grub
activity. The trap also helps to reduce the number of egg laying
adults in the surrounding area. Each trap is supplied with a powerful
pheromone, which attracts male Garden Chafer beetles.
Key
points:
- The trap will be set
in May and will be hung 50 - 100cm above ground level. There will be several
traps around the problem areas. Mainly around the 14th and 15th
fairways.
- One trap will cover
2000m2 or half an acre.
- The trap is supplied
with pheromone bait which lasts for up to 6 weeks.
I
hope this gives you an insight on what we are doing to get on top of this
problem for next year.