opinion

Temporary Lake O Roundup ban no magic bullet — but that's why it's the right call

Let’s not get too excited.

The decision by the Florida Fish and Wildlife Conservation Commission last week to temporarily suspend the use of aquatic plant killers, including the controversial herbicide Roundup, to control weeds in Lake Okeechobee and other state waters was undoubtedly good news.

There are significant concerns about glyphosate, the active ingredient in Roundup, and its potential impact on human health. One widely-cited 2015 study by the International Agency for Research on Cancer calls it a potential carcinogen; and the widespread use of glyphosate in commercial agriculture means trace amount of the chemical inevitably make it into the food we eat — with potential consequences not yet fully explored.

More: Should Martin County ban Roundup? | Gil Smart

More: Why is FWC feeding Lake O algae with Roundup?

But the more immediate problem might be glyphosate's potential impact on our waters. For glyphosate, widely and effectively used in Lake O and elsewhere to kill invasives such as torpedo grass and water hyacinth, ultimately deposits phosphorus into our waters.

Not only that, the plants killed by the chemical often sink to the bottom, turn into sediment — and release yet more phosphorus into Lake O and other waters.

Phosphorus feeds the blue-green algae blooms that choked local waters in recent years. So unquestionably, both glyphosate and the manner in which it is utilized have resulted in more phosphorus in our waters — and, ultimately, more blooms.

So the temporary ban by FWC is the right call.

But we shouldn’t delude ourselves into thinking it’s the magic bullet, because where this problem’s concerned, magic bullets don’t exist.

Research suggests some 2.3 million pounds of phosphorus found its way into Lake O in 2017. The amount of phosphorus deposited into the lake as a result of Roundup sprayed by FWC: 2,943 pounds.

And even if you were to somehow factor in the phosphorus contributed by the plants killed by the glyphosate, we’re talking pennies to the hundred-dollar bill.

Yet specifically because there is no magic bullet, the FWC decision to suspend application — and convene public meetings to seek input on new, presumably more restrictive herbicide use — are not only the right call, they’re a necessary call.

Yes, glyphosate is only one small part of the problem. But as noted, given the complexity of the problem, and the inability to find the “big” solution, the only available remedies are small solutions.

The FWC move amounts to one such small solution. And as such — it’s key.

To be sure, there may be a cost to it. Glyphosate is ubiquitous because frankly, it works.

It's used by commercial farmers who spray it on some crops near the end of the growing season to expedite the usual process whereby the crop dies and dries in the field. That allows farmers to clear the fields before the onset of unfavorable weather, and reduces the moisture in grain crops to enable them to be more easily stored without getting moldy.

That increases yields, and ultimately profits.

Roundup is also highly effective in controlling weeds on Lake O. Without spraying, said Paul Gray, a wetland ecologist with Audubon Florida who's been studying the lake for more than 20 years, invasive plants could choke out native vegetation on Lake Okeechobee and block boaters' access to the lake's marshes.

Moreover, failing to control invasive weeds could itself contribute to algal blooms, as invasives such as water hyacinth and water lettuce shed old and damaged leaves, which release phosphorus into the water.

"The question is: What's the right amount?" Gray said.

That’s what the FWC meetings, and public input, will seek to address. Though those meetings haven’t yet been scheduled, those who wish to get a jump on the process may email comments about the agency’s herbicide spraying policies to: Invasiveplants@MyFWC.com.

Whatever the new rules look like, however much glyphosate ultimately is or isn’t used to control weeds on Lake O and other state waters, the algae blooms may well continue. This won’t stop it.

But if our algae problem is ever to be definitively solved, we will need dozens — perhaps hundreds — of small solutions. Not to mention the political will to seek and implement them.

So let’s be clear-eyed about the fact this move by the FWC is not enough to get us to our destination.

But when it comes to protecting our waters, every little bit helps.