A sugar exchange traded note jumped over its short-term trend line Monday, with sugar prices hitting a four-week high as traders take bearish bets on poor weather conditions in Brazil, a leading producer of sugarcane.

The iPath Dow Jones-AIG Sugar Total Return Sub-Index ETN (NYSEArca: SGG) rose 3.0% Monday, crossing its 50-day simple moving average. The ETN, though, has declined 18.4% year-to-date.

Brazilian harvests have been delayed as rains cover Brazil’s central-south region, the main sugar producing area, reports Emico Terazono for the Financial Times. Traders are trying to hedge against a loss of sucrose in the cane, which would hinder sugar output.

“We’re picking up some short covering,” Michael McDougall at commodities broker Newedge, said in the Financial Times article. “The volumes are quite big.”

Sugar futures were up 2.7% Monday, trading around $16.9 per pound, a four-week high.

Moreover, concerns over frost damage to sugar canes has also weighed on investors after about two years of large harvests coming out of Brazil. Frost would “shock” the plants into flowering and reduce yields.