Hawaii’s congressional delegation on Thursday introduced bills to promote the health of macadamia trees, one of the state’s most valuable crops.

All four of Hawaii’s elected officials in Congress sponsored bills for the Macadamia Tree Health Initiative Amendments Act, which would attempt to address pests and weeds that impact the macadamia tree and study its biology by expanding grants for related research.

“Macadamia nuts were first planted in Hawaii in 1881 and have become a signature crop that Hawaii is known for around the world,” U.S. Rep. Jill Tokuda said in a joint news release. “Facing ever increasing threats, this bill will ensure that the industry is well- supported and contributing to our local economy for years to come.”

The bills would support the development of tools and treatments to combat plants and weeds that affect macadamia nut trees; establishment of a management program in areas affected by invasive plant pests or weeds; data collection on macadamia tree nut health and production; and research on factors that may contribute or be associated with macadamia tree immune systems and other threats to the crop.

The U.S. Department of Agriculture reported in 2017 that only seed crops were more profitable in Hawaii than macadamia nuts, which were found to be more valuable to Hawaii agriculture than coffee, cattle or algae.

In 2021, 51 million pounds of the nuts were harvested in the state across 17,000 acres of land, up 28% from the previous year, according to the USDA. Although disease, insects and feral pigs damaged macadamia nut orchards in Hawaii, the agency said the economic impact was minimal.

Hawaii’s congressional delegation introduced similar bills in 2021, although those bills failed to become law.

At the state level, lawmakers have introduced bills that would clarify the origins of macadamia nuts sold in Hawaii on the product packages. The bills would protect Hawaii’s macadamia nut industry, advocates say.

The Hawaii Farm Bureau, in written testimony supporting one of those bills, said one of the greatest threats to the viability of macadamia farming in Hawaii is “the misleading labeling of macadamia nut products. Currently, there is little to no regulation to prevent the use of Hawaiian names and images to market macadamia nuts grown outside of Hawaii, the bureau said.