MANKATO — This story starts with a comment card.

Filled out two years ago by a concerned parent and sent to a school administrator.

The kind of comment card that gets lost in the shuffle of dirty plates and silverware on restaurant tables. The kind that lines the suggestion box until management unloads them into a wastebasket. The kind that might be scanned, glanced at or reviewed — but never really read.

But this particular comment card spawned a series of events that is still unraveling.

The comment was about herbicide-spraying schedules on school grounds during the summer. Mara Natrakal, a green-wise mother of three children living in the Mankato Area School District, had heard about the health hazards of herbicides and pesticides. And she simply wanted to make sure that children using school grounds for summer activities wouldn’t be exposed.

“The superintendent saw my comment card,” Natrakal said. “And after that, things started happening and we began learning so much more.”

The comment card eventually landed in the hands of district health and safety coordinator Joe Meixl. And he was interested in hearing about Natrakal’s concerns.

After asking Natrakal if she would be willing to help with leg work and committee functions, Meixl received a $40,000 grant from the Minnesota Pollution Control Agency to run a two-year test on the effectiveness of organic herbicide alternatives.

The testing began in summer 2006 with plots at West High School and Garfield and Monroe elementary schools. The district compared traditional methods with two organic alternatives: corn gluten and dried distillers grain. During the experiment, officials found both organic alternatives fared as well or better on weed control as standard measures and that both were healthier for the soil.

Now, after two years of testing, Meixl is analyzing the data and trying to formulate revisions to the district’s weed control and turf management strategies.

“At this point, the project is still being summarized,” Meixl said. “But what we’d like is to eventually have all public school spaces designated as chemical free.”

But there are some challenges — namely, cost.

The price of corn gluten has skyrocketed in recent months. One year of corn-gluten applications for the district would cost about $50,000 — or roughly 10 times what the district now spends on synthetic weed sprays. Dried distillers grain, which is relatively untested compared to corn gluten, also is more expensive.

The real valuable information, Meixl said, came in the form of “cultural practices” — simple, preventive measures such as periodic overseeding, better irrigation and annual aeration that district officials learned more about indirectly during the experiment.

These practices, Meixl said, help maintain turf health and nutrition. And they are far less expensive and perhaps more feasible than pricier weed-control strategies.

“Healthy soil grows grass, not weeds,” Meixl said. “Cultural practices help maintain the soil over time and can be implemented pretty easily.”

Meixl has prioritized the district’s grass areas. Highest priority is given to athletic fields and high-use areas and low priority is assigned to general areas around buildings. The idea is to focus practices where they’d be most useful.

Eagle Lake Elementary has even been designated as the district’s first organic campus.

“They are not even using Roundup on the sidewalks,” Natrakal said. “Which meant I had to hand-pick some of the weeds before they got the organic weed killer.”

In the course of the two-year test, Natrakal met with turf experts, attended seminars, sat on committees and learned more about grass than she ever imagined.

And while Natrakal said there is more work to be done, she’s satisfied with the work accomplished through one little comment card.

“In Minnesota, we often view herbicides and pesticides as an environmental issue,” she said. “But people need to realize it’s a public health issue, too.”