There are many kinds of bugs that can damage or even destroy parts of your lawn such as the grub of the Japanese beetle. While they may be out of sight underground, their appetites for turf roots cannot be easily satisfied. As a result, browning usually occurs all the way to large areas of dead grass in the spring or fall. How can you save your lawn? Can this evil beetle and its associates be stopped? Take a deep breath as we take a closer look at this villain and his underground buddies.
To begin with, you must start with the environment. Grubs live underground therefore they are considered a subsurface insect pest, as opposed to a surface one- such as a chinch bug or perhaps cutworms. This is important because what method and material you may use to target the grubs underground is vital. So let us move onto timing. When can you kill them? Well, there is curative- you have grubs and they need to die now or preventative- you may have them or are likely to in the future so you treat ahead of time as insurance.
Before you treat anything, ask yourself a question. Do you really need to do this? Many lawns will tolerate minor grub infestations and do just well. Just because you found a few in your mulch beds or garden while digging does not make for an alien invasion or epidemic! An average lawn will tolerate grub feeding and not all grubs eat turf. So, before you pull out the tank and flame thrower, ask for some professional advice or at least consider the multitude of choices available.
Grub control products have progressed a great deal in the last few decades in terms of effectiveness, amount of active ingredient required, ease of application, and environmental impact. Before I proceed forget about Milky Spore, it does not work in New England and should be outlawed. Most registrations have elapsed or are revoked which is why there is only a few on the market even though there should be NONE. There is not a shred of scientific evidence or proof that one grub can be killed by this magical elixir in NH or VT. While I normally do not take such a harsh stand on a topic, I simply cannot stand on the side line while people throw their hard-earned money. Both Universities in NH & VT agree with this statement since it is at their training seminars that Milky Spore is akin to curing all of your aches and pains with just one teaspoon of “Uncle Jacks wonder tonic”. Let us move onto more productive conversation.
There are a handful of different materials that will virtually decimate a grub population when used properly. Many of these control products are only required in small amounts and last months because they are taken into the grass plant up through the root system. As a result, these control products are very effective and pose a minimal risk to user and the environment. One new product in particular does not even require a signal word (Danger/Warning/Caution) this is unheard of in the turf or agricultural industry. Most of these products can be applied alone or blended with a fertilizer for improved results. Some studies show that with proper irrigation, soil moisture, and fertilizer- a lawn is better protected due to the ability of the grub control material to be readily taken into the turf via the root system.
Most preventative control products can be applied from late May all the way into September in some cases. The stage of the grub and the material chosen is imperative because not all will work at specific times or stages. This would be like trying to stop an elephant with a broom, it just is not going to happen verses say a bulldozer- the tool being used and the timing is very important.
Nematodes are being bred and are being touted as a very effective organic if not biological control of not only Japanese but dozens of other beetle grubs. I plan on using nematodes this year in my program and have done enough research to at least give them a try based upon my findings. If stuff does not work, I just won’t use it- period. Sorry, but clients do expect results. There are lots of important things which must be done in terms of timing, watering, volume etc- but there is no denying these boys are chemical free! I will report back in a later post the results and findings of how these treatments went later this summer.
Now is the time to research and have your lawn treated if you have had grub damage or problems in the past. Remember, adult Japanese beetles are very difficult to control since they are strong flyers. Good hunting.
The following link sums up the importance of timing and life cycles when selecting control products: