Lincoln Square Alderperson ‘Beyond Frustrated’ As Welles Park Grub Infestation Continues

LINCOLN SQUARE — Lincoln Square’s alderman is concerned the Park District’s attempts to control a damaging beetle infestation at Welles Park don’t seem to be working.

A contractor hired by the Park District treated the fields for the infestation in the spring, after a beetle grub outbreak damaged the grounds yet again.

Despite this, swarms of the adult beetles have been seen at the park since at least July 6. 

“I am beyond frustrated that the Welles Park grubs hatched into what seems to be thousands of adult beetles — just weeks after a Park District contractor said treatment for grubs had been completed,” Ald. Matt Martin (47th) said in an email to Block Club. 

Martin said he first brought his concerns to the Park District in the fall. He worried the grubs could again damage Welles Park in the spring, he said. 

“At that time, Park District leaders assured me that was not the case, but months later, just before the start of summer programming, the fields were closed again for treatment,” Martin said. “I have shared my serious disappointment with Park District leaders regarding these ineffective treatment plans.”

The Park District entered into a $6 million, two-year contract with Christy Webber Landscapes and its subcontractors at a Dec. 10 meeting to oversee the park system’s planting, landscaping, turf and athletic field services, according to district records. 

On March 9, Stacey Anti, Park District north region director, wrote in a letter to park “stakeholders” saying their landscape crew had found a “grub infestation” at Welles and Winnemac parks and they had “scheduled with our contractor, Christy Webber Landscapes, for grub treatment and reseeding to begin mid-April. This is the earliest date as this work is weather dependent.”

Christy Webber Landscapes applied a treatment of the pesticide Acelepryn at Welles Park this spring, Park District spokesperson Irene Tostado said.

The green June beetles residents are seeing now are the mature, adult stage of the grubs seen this spring at the park, said Tostado, who noted the bugs “aren’t harmful to people.”

Tostado said the current “revised plan” is to apply repeated treatments of the chemical to the grounds in the late summer and early fall, when the bugs are in “a vulnerable stage in their lifecycle.”

Martin said he will talk with the Park District regarding its “revised plan” to make sure “the grubs issue is resolved in a more permanent way.”

Matthias J. Scheidler, who works at Christy Webber Landscapes as its maintenance department director, referred questions about the revised plan and the alderperson’s concerns to the Park District. 

There could be a variety of reasons the treatments have yet to be effective, state entomologist Christopher Dietrich said Tuesday.

Dietrich said the active ingredients in the insecticides used in the spring and in a 2021 grub infestation only work if they come in contact with the insect or are ingested.

If the treatment is applied too early in the spring, the grubs could be too deep underground to come in contact with it. Or heavy rains just after the chemicals are applied could wash them away or dilute them, lowering their effectiveness, Dietrich said.

Alternatively, if the treatment is applied too late in the spring, most of the grubs may already be at the pupal stage. At that point, the bugs are enclosed in a cocoon made of soil glued together by their own secretions, possibly making them less vulnerable to exposure to the chemicals, Dietrich said. 

Another possibility is the beetles came from somewhere else. During a summer heatwave, for example, a well-watered ball field may be too good a home to pass up for female beetles looking to lay a clutch of eggs, Dietrich said. 

“You can’t completely rule out the possibility that the beetles that are swarming in the park now migrated in from some nearby population that wasn’t treated with insecticide,” he said. “The adult beetles are capable of flying over a considerable distance.”

But good news could be on the horizon. Dietrich said the green June beetles at the park appear to be more susceptible to late summer treatments aimed at preventing a new generation of grubs from making it to adulthood. 

Predation by other critters, like parasitic wasps, could also help reduce the population of beetles, Deitrich said, although he warned chemical insecticides could negatively impact natural enemies and beneficial pollinators. Pigeons were seen in the fields Monday afternoon pecking away at the bugs.

“These and similar pesticides are supposedly not toxic to birds and other non-insect wildlife if they are used correctly. But extended exposure and ingestion of large quantities can result in adverse effects,” Dietrich said. 

In general, though, combatting grubs won’t be a simple task — and could continue to be a years-long ordeal.

“It’s often not easy to bring such heavy infestations under control and they often require several treatments over multiple years,” Dietrich said.