A weekslong strike at Deere & Co. has dealers bracing for delayed deliveries of new equipment, and farmers fearing higher prices ahead.

Supplies of new tractors and combines across the Farm Belt have been stretched for months as manufacturers struggle with shortages of raw materials, components and semiconductor chips. Now, farmers and dealers worry that shipments from Deere, the largest seller of farm equipment in North America, will be further undermined after more than 10,000 union workers walked off their jobs Oct. 14....

A weekslong strike at Deere & Co. has dealers bracing for delayed deliveries of new equipment, and farmers fearing higher prices ahead.

Supplies of new tractors and combines across the Farm Belt have been stretched for months as manufacturers struggle with shortages of raw materials, components and semiconductor chips. Now, farmers and dealers worry that shipments from Deere, the largest seller of farm equipment in North America, will be further undermined after more than 10,000 union workers walked off their jobs Oct. 14. Members of the United Auto Workers union this past week rejected a second proposed contract, deepening uncertainty during the fall harvest season about when regular production may resume.

Farmer Dale Reimers, who grows corn, soybeans and other crops across 25,000 acres in eastern North Dakota, said he ordered three new Deere tractors and two crop sprayers before the strike. Delivery for some equipment already has been delayed for months, and it is unclear when the rest of his order will even be built, he said, adding that he worries the strike could further complicate things.

Deere said the contract rejected Nov. 2 was the company’s best and final offer.

Photo: Charlie Neibergall/Associated Press

Late delivery of his sprayers could cut into his crop production next year, Mr. Reimers said, because his older equipment can’t apply weed-killing chemicals to fields with the same precision as the new machines he ordered.

“That’s going to have a big impact on profitability and production results on the dirt level,” said Mr. Reimers, who relies exclusively on the company’s equipment.

Moline, Ill.-based Deere declined to comment on equipment inventories and deliveries. Deere has said it would continue operating its U.S. plants with supervisors and other nonunion employees, and that the company is considering sourcing replacement parts and machinery from its overseas plants. Dealers said they have been getting some equipment from Deere factories as nonunion workers put the finishing touches on machinery that had been parked at assembly plants waiting for parts to arrive.

U.S. farmers are riding a rebound in the agricultural economy this year, fueled by a rally in prices for major agricultural commodities such as corn and soybeans. That is pushing up incomes for farmers and boosting markets for land and equipment, though rising production expenses are cutting into profits, farmers say.

The U.S. Department of Agriculture in September projected net farm income would surge 20% this year to $113 billion, the highest since 2013. It said farm production expenses would increase by more than 7%.

The reinvigorated farm economy is driving demand for new equipment. Over the first three quarters of Deere’s current fiscal year, its sales climbed 27% over the prior year, and net income more than doubled to $4.7 billion. Deere expects to earn about $5.8 billion for the full year. Deere’s shares Friday closed up 1.2% at $355.20.

Union members have said that the raises and expanded benefits Deere has offered aren’t sufficient when sales are booming and other companies are boosting wages and offering new perks to draw workers. Deere this past week said the contract rejected Nov. 2 would have represented a $3.5 billion investment in its employees over six years, and was the company’s best and final offer.

Deere dealers said they have already this year managed through shortages of replacement parts and equipment caused by disrupted supply chains that have slowed production and deliveries.

Farmers’ demand for equipment has remained strong in 2021, and new equipment shortages have led farmers to shop the used market. Dealers said a prolonged strike will increase prices and demand for used machines.

“It’s a really bullish market for used equipment,” said

Tom Sloan, chairman of Sloan Implement Co. in Illinois. “Normally, we have too much.”

Mr. Sloan said some buyers who normally turn over their older equipment to dealers as trade-ins are now keeping their equipment, as the Deere strike adds to uncertainty over the delivery of their new machines.

Farmers often sink profits into new equipment annually because they can deduct those purchases from their federal income taxes as business investments. A lack of equipment kept some farmers from buying this year, said Robert Klemm, who grows corn and soybeans in Illinois and runs an agricultural tax-planning and preparation firm.

“It’s a chain reaction,” said Mr. Klemm. He said having parts available from factories and dealerships is also vital during the fall harvest, when agricultural machinery often breaks down and farmers don’t have 30 to 60 days to wait for supplies to be replenished.

Farmers placing orders through Deere’s early ordering program that started in August typically get their equipment in January or February. Blue Riggan, owner of Legacy Equipment LLC, in Arkansas, expects that delivery times will be extended the longer the strike lasts.

“If they go out for a long time, it would probably push us out until March or April,” said Mr. Riggan, referring to striking workers.

Deere dealers say the strike hasn’t caused their customers to defect to rival brands because competitors remain constrained by their own supply and production problems. CNH Industrial NV, the maker of CaseIH equipment, pared its 2021 sales guidance on Thursday because of ongoing supply-chain problems.

“‘It’s just one part of 1,000 problems this year.’”

— Brian Herringshaw, who runs his family’s farm in Ohio

Deere has been raising prices on equipment, upping the price tags on early-order equipment for next year by 8%, the company said during its last call with analysts in August. JP Morgan estimated Deere would have to raise prices an additional 1.5% to cover the higher labor costs in the six-year offer Deere workers turned down Tuesday.

Brian Herringshaw, who worked as an engineer at Deere for eight years before leaving in 2016 to run his family’s farm in Ohio, said rising machinery prices will add to farmers’ other escalating costs, which span from fuel to fertilizer this year.

Mr. Herringshaw said high prices for used equipment had already deterred him from purchasing a planter and tractors, and that a run-up in machinery markets or supply disruptions stemming from the strike would compound farmers’ challenges.

“It’s just one part of 1,000 problems this year,” he said.

Write to Jesse Newman at jesse.newman@wsj.com and Bob Tita at robert.tita@wsj.com