- Author: Ryan Daugherty
I was dealing with a gopher problem in a lawn awhile back and I came across another turfgrass pest that you may or may not be familiar with; a chafer beetle.
These white grubs are the immature larval form of a chafer beetle.
Here in California we deal mainly with the masked chafer (Cyclocephala spp.). Mature grubs have white or cream colored, C-shaped bodies, six legs on their upper half, and a chestnut brown head. They can be confused with the somewhat smaller black turfgrass ataenius larvae (Ataenius spretulus). To identify the difference between the two, look at the tip of the abdomen (the opposite end from the head) for the arrangement of bristles and overall anatomy, we call this the raster pattern. A chafer's raster will have a transverse anal slit with an indistinct pattern of bristles all over. An ataenius will have two distinct pad-like structures on the tip of the anal slit.
The chafer grubs feed on turf roots in early spring then stop around May to pupate with adults emerging around June to mate. Adults actually have non-functional mouthparts and so do not cause feeding damage, in fact they die of starvation shortly after laying eggs. Adults are about 3/4 inches long with golden brown bodies and they emerge during the night with a strong attraction to light. If you see adults during the summer, eggs are likely being laid in your grass. Eggs hatch around August and the grubs do most of their damage in September and October before moving deeper into the soil to overwinter until the spring.
Damage looks like drought symptoms in turf: brown, blueish, or gray spots, brittle straw colored grass, thinning stands, and footprinting. These symptoms are from the extensive root feeding of the grubs as the grass loses much of its ability to take up water. You may also see vertebrate feeding from birds or skunks that can cause further damage digging for the grubs. Spots of affected turf may be small, only being a foot or two across but may combine with other spots to form large sections of damaged turf. A hallmark of grub damage is that damaged turf can be peeled back from the soil like a carpet, due to the turf having no roots.
Insect damage in home lawns is rarer than you might think, with abiotic problems like poor irrigation, mowing, or fertility practices being a more likely culprit for a struggling lawn. If there is an insect pest make sure you correctly identify the insect before intervening with any control measures. Also remember that the presence of a pest doesn't always necessitate control. A healthy lawn can withstand damage from a few grubs and a robust lawn is always the best defense against pest damage.
Damaged turf can be helped by irrigating more frequently to keep soil moist around the lawns now shallow roots. Lawn aeration can also kill segments of grub populations. Reserve any kind of chemical intervention until you see 6 or more grubs per square foot. Several insecticides are available on the market for chafers or white grub control just look at the label. UC IPM has a page dedicated to masked chafers, but keep in mind the pesticides recommended there are for professionals.
Always read and understand the label of any pesticide you intend to use. Be careful to refrain from applying insecticides (especially broad spectrum) if there are flowering plants in and around the lawn; this includes weeds like clover or dandelions as it can harm beneficial insects like pollinators that may come into contact with them.
- Author: Dustin Blakey
The real estate market may not have returned to its pre-bubble days, but there are signs of life in the home market. I have noted a few homes in my neighborhood that have changed owners. This usually means activity in the landscape, and not all of it is beneficial.
When new owners move into a house, they are often presented with a landscape that at best isn't what the new owners would have chosen, or at worst has been neglected for a considerable time.
Perhaps it's the pride of ownership, but many times new owners feel compelled to so something in the landscape. For better or worse, work must be done, or so it seems to be thought.
It is very common to see new homeowners hack back their trees and shrubs, scalp their lawns, and put in too many new plants, often of the wrong kind.
A study of tree topping (Fazio and Krumpe, 1999) found that 26% of people who topped their trees had been in their home 4 years or less. The remaining 74% had been there between 5 and 70 years. These numbers strongly suggest that new homeowners are motivated to act on their yard with the best of intentions.
Probably the best advice I can give is to hold on, take a deep breath, and work on something else first. Use this time to research all your options in the yard. Bad choice can reduce property values and create future liabilities.
When you move into a new house and are faced with managing an existing landscape, follow these tips:
- Do not severely prune your trees and shrubs. Trees and shrubs may need some care, but topping (arbitrarily cutting back limbs and branches) will disfigure your tree/shrub and may lead to future problems. Consult a Master Gardener or arborist to determine a good course of action. A tree service that suggests topping is not following recommended practices. The best tree companies don't usually knock on doors.
- Rake leaves, remove debris, and prune off limbs and vines interfering with the mechanical operation of your home. Remove plants and debris that are a fire hazard.
- Start a compost pile for yard waste.
- As soon as possible, check sprinklers to ensure they are working as expected. If you are unfamiliar with irrigation, this is probably a job best hired out. A spring set-up of a sprinkler system is not expensive. If you pay for metered water, it usually pays for itself in a season in water savings. They can show you how to set your sprinkler times as well. If, after irrigation, the street is wet or if you see "Old Faithful" erupting in your yard, your system needs attention for sure.
- Do not plant trees and shrubs without researching whether it is appropriate for your location and climate, and whether it will fit into your landscape as a mature specimen. Many trees get surprisingly large with age!
- Do not plant trees under power lines.
- You may need to mow some overly tall turf. If this is the case remove the clippings from the lawn and compost them; however, it is best to mow frequently enough that you never have to bag clippings. Bagging clippings removes nutrients from the lawn that are best left there. If you are leaving globs of grass on the lawn either mow more often or consider raising your mowing height a little to see if that helps.
- Don't over use fertilizers or pesticides. Read labels.
Enjoy your new home, but remember to resist the urge to act now! Most landscape work can wait until you've done a little research. Our Master Gardeners can give you research-based answers.