The City of Vancouver and the Vancouver Park Board are asking residents to help keep alive younger trees in the city that may be suffering in the extended hot and dry conditions this summer.

"We're appealing to the public to give us a hand if they don't mind," said Howard Normann, the director of parks for the City of Vancouver.

A young City of Vancouver street tree, one of up to 2,500 that are planted each year, equipped with a special water bag. (Stephanie Mercier/CBC)

"If they see a tree in front of their home that needs a drink ... maybe spend a few minutes and use their hose and give it a bit of a soaking."

Leaves on trees turn brown and drop off as a defence mechanism by the plant to conserve water.

If residents are unable to directly water trees, they can report trees in distress by using the VanConnect app or by calling 311.

There are six watering trucks currently being double-shifted to get out to trees in distress.

Normann says around 4,000 special water bags have been attached to trees to help give long drinks. That's double the number from last year.

"The bags are refilled every two days," said Normann.

Vancouver has been in a tree-planting blitz as it tries to increase the city's canopy cover — the area covered by tree leaf canopies — from 18 to 22 per cent.

Tree math

Vancouver park trees: 350,000.

Vancouver city trees: 150,000.

Number of new trees to be planted by 2020: 150,000.

New street trees planted each year: 1,500 to 2,500.

New park trees planted each year: 7,000.

Normann says, trees planted in the past four years are most susceptible to drought.

"[Newly planted trees] drink a lot of water. At least for the first three years, so those are the ones we're on top of right now," said Normann.

There are around 4,000 tree water bags deployed in Vancouver to help keep trees from dying from drought. In the summer they are refilled every two days. (Stephanie Mercier/CBC)

Still, he said if Vancouver faces consecutive dry summers, mature trees could soon be suffering too.

"At this point we've been very fortunate that trees tend to be doing OK, the big ones, but if this is an ongoing thing for several years it could be more problematic for us."

Vancouver has had zero rain in August so far. In July, only 1.8 millimetres fell according to Environment Canada.