One of the largest tree-planting exercises in B.C. history is in jeopardy due to drought.

Many in the know are worried because the newly planted trees — roughly the size of two toothpaste tubes stacked together — are vulnerable to the parched conditions.

This year’s planting is one of the largest on record, with 265 million seedlings worth about $265 million, and comes as record dry conditions impact particularly the southern parts of B.C.

There is anecdotal evidence that thousands of year-old seedlings have succumbed to the unprecedented conditions.

“Some of our main local customers are seeing areas of heavy mortality,” said Jody Branter, nursery manager at PRT Hybrid in Pitt Meadows, a large commercial grower.

Marilyn Curtis, customer support rep at the nursery, said the drought has likely taken a significant toll.

“We’re hearing about a much higher mortality rate than what the customers are used to. I’ve been in the business 40 years and this is the hottest, driest summer I’ve ever experienced,” she said.

The province’s 2015 replanting program was one of the largest ever, costing some $265 million and encompassing 190,000 hectares.

Work began at lower elevations in late March, before the drought began.

The province’s forestry branch admitted there is a drought-related “risk” and some “plantation failures” have probably occurred.

Al Powelson, B.C.’s stand management officer, said it will take up to six months to find out exactly what happened.

“The general practice is to do a walk-through this fall and see if they are still alive. A formal assessment is made next year to see if the trees wake up when they’re supposed to,” he said.

“I’m not overly worried,” he said. “What could happen is you lose a year.”

Trees are vulnerable from the time they no longer receive regular watering at the nursery until their root systems are established in the wild, said John Betts, executive director of the Western Silvicultural Contractors Association.

“They need to get moisture quickly. If they don’t, they’re dead. There is always a risk in this form of agriculture. You plant a site in April and you don’t know that it’s not going to rain for several weeks,” he said.

“The planters did everything they could. If seedlings had been left in the reefer, they’d be dead for sure. I’m sure the licensees (wood harvesting companies) are paying very close attention. We’re all concerned,” he said.

Despite the unprecedented lack of precipitation, some are hoping for the best, especially in the north, where precipitation was higher.

Curtis said the trees’ resilience can be “surprising.”

“They can put down roots, shut down for the summer and go into a holding pattern. Anything in shadow throughout the day is going to fare better,” she said.

“We’ve seen all kinds of things. If the mortality rate is higher than usual, I expect additional seedlings will have to be grown to cover that mortality. The industry will just have to work through any problems which arise,” she said.

Powelson said companies are responsible for returning forests to their natural state, so bare patches must be planted again and the costs absorbed by private industry.

“The companies have the legal responsibility to reforest. It’s a risk everyone has,” he said.

B.C. taxpayers would be on the hook for government programs which sponsored 65 million trees, at a cost of roughly $1 per tree.