Although proper turfgrass maintenance programs can greatly reduce the invasive pressures of the various turfgrass weeds, even the highest quality turfgrass areas will occasionally be invaded by one or more weed species. While a few weeds can be physically removed, considerable weed encroachment may require chemical controls.
There is an age-old suggestion to lower mowing heights in the fall to avoid turf diseases developing during the winter. This is not necessarily accurate. Ohio State University turfgrass specialists say that it is more important to KEEP MOWING until the grass stops growing for the season.
There are a couple of key maintenance operations to perform in the fall to help turfgrass survive the winter and support early spring growth. Three important operations are (1) late season fertilization; (2) coring/aerification; and (3) dormant over-seeding.
Joe Boggs reported that fall CRANE FLIES (Tipula spp.) are rising from turfgrass in southwestern Ohio. They look like giant, mutant mosquitoes; a startling image outside of a sci-fi movie. Fortunately, crane flies do not possess mosquito-like piercing mouthparts, so they do not bite. However, large numbers of crane flies flittering above lawns can be a real nuisance, particularly when they find their way into homes.
Randy Zondag and Tim Malinich reported that they had some surprising finds during their last Diagnostic Walkabout. While digging grubs for the class to identify, they expected to have a very similar grub population as previous years--lots of JAPANESE BEETLE (Popillia japonica) with the possibility of one other grub showing up for variety.
Marne Titchenell has received several reports of mole damage to lawns across Ohio. Spring and fall are when moles are most active, as the ground is moist and easier to tunnel through. EASTERN MOLE (Scalopus aquaticus) damage is identified by raised tunnels just below the surface.
Dave Shetlar reported spotting patches of turfgrass that had been pulled-up. The symptoms looked a bit like skunk or raccoon grub-foraging damage; however, Dave noted that further observations revealed the true culprit: crows! He found that the crows were indeed going after MASKED CHAFER (Cyclocephala spp.). A close examination further revealed that about 50% of the chafer grubs were in the 2nd instar stage and the remaining 50% had reached the early 3rd instar stage.
An interesting turf puzzle was called into one of the local Extension offices. The caller had planted a new lawn several years ago using turf-type tall fescue. Now, the somewhat coarse stand of tall fescue is dotted with clumps of weedy tall-fescue. It seems the clumping, very coarse weed had gone unnoticed in the turf-type tall fescue lawn until it had spread over much of the lawn.
Dave Shetlar and Joe Rimelspach reported the occurrence of gray leaf spot fungus (Pyricularia grisea) in perennial ryegrass (Lolium perenne). Gray leaf spot infects and can cause death of grass blades. In severe infections, the fungus can move into the grass crown and kill the entire plant.
This means the most damaging stages (late instars and adults) of this turfgrass pest will not appear until sometime in September ... just in time to wreak havoc on newly planted turfgrass! Chinch bug damage usually appears as browned turf occurring in irregular patterns and the symptoms may be mistaken for high temperature dormancy, drought stress, or even certain turfgrass diseases.