A new type of soybean seed that allows farmers to spray more herbicides on their fields was cleared for import by the Chinese government last month with great fanfare. However, the seed’s sale will likely be held up past spring planting because of a pending approval from the Filipino government.

Enlist E3 — featuring a genetically modified set of traits that makes crops resistant to three key herbicides — was developed by DowDuPont spinoff Corteva Agriscience and will allow farmers to mix a more potent cocktail of chemicals to spray on their fields.

“Soybean farmers are facing challenges in terms of weed control,” said Denise Thiede, who works in plant protection for the Minnesota Department of Agriculture. “Weeds are evolving tolerance to Roundup.”

Several types of commercial soybean seeds are already immune to herbicides made with glyphosate and glufosinate, which are sold commercially as Roundup and Liberty. What the new Enlist seed would offer is a soybean that’s also immune to 2,4-Dichlorophenoxyacetic acid — or 2,4-D — another weed killer manufactured by Corteva.

Being able to plant soybean seeds that allow for spraying of all three types of herbicide is something farmers are looking forward to.

Alan Muhs, soybean production manager for NorthStar Genetics, based in Wanamingo, Minn., said Enlist is often the first thing farmers ask about when they call him.

“This will be the first triple-stacked soybean trait in the market,” Muhs said. “There’s been an excitement for this thing for a long time.”

When the government of China approved the genetically modified soybeans for import in early January, farmers and seed companies hoped they would be able to buy the seeds ahead of spring planting.

But that’s looking unlikely, thanks to the fact the seed has not been approved for import yet by the Philippines.

“Before the big holdup was China. Now, the one kind of laying in the weeds that nobody was talking about is the Philippines,” Muhs said. “May’s the time frame I’ve been given, but they’re not too confident.”

A Corteva spokeswoman declined to say when Enlist E3 soybean seed will be for sale.

Companies cannot release a seed for sale before it gains approval in all export markets because of the risk that a country that has not given approval will reject boatloads containing a crop grown using that seed.

“That is one of the challenges with all genetically engineered traits,” said Thiede, of the Agriculture Department.

Switzerland-based Syngenta was sued in 2014 by farmers across the central U.S. after it launched sales of a genetically modified corn seed before it received approval from the Chinese government.

Farmers claimed they suffered losses because the price of U.S. corn dropped when China began rejecting shipments of corn grown using that seed.