THE LEAFLET

July 16, 2018 /
Jona Elwell

Night Farming at the Casey Tree Farm to Beat the Heat

Farming doesn’t stop because the sun sets or the clock hits a specific hour. And last week, thanks to the absolutely brutal temperatures and heat index, the bulk of care on the Casey Tree Farm took place during some unusual hours.

Night farming! Just like humans, trees sweat out water. They’re able to expend energy transporting water through their roots, trunks, branches and eventually out of their leaves.  While this process is very beneficial, it does have its limits. If the ground is very dry, the tree struggles to keep up demands from the leaves for water and nutrients. The first line of defense against high temperatures and moisture loss is for the leaves to close their gas exchange holes, known as stomata.

While this dehydration defense mechanism works to conserve energy for trees, it makes applying fertilizer challenging, since the tree is less likely to absorb the needed nutrients. On top of that, watering when it’s 90 degrees out is an exercise in futility, as the majority of the water evaporates before the tree is able to absorb it into its leaves and roots.

What’s a farm trying to grow healthy trees to do? Reid Kemp, our Nursery Assistant Manager explained, “We’ll give trees foliar fertilizer applications in the early early morning, before the sun and heat really ramp up, but also when the trees are most ready to absorb them.”

Something more important for humans? The temperatures are tolerable. The cool(er) nights create better working conditions when the team doesn’t have to worry too much about heat exhaustion, dehydration, or sunburn.

That doesn’t mean all hazards are removed though – working at night has its own challenges. Many safety risks of night work in agriculture are the same as the risks of daytime work, but they may be exacerbated by night conditions, such as limited visibility due to poor lighting. Or even nocturnal animals.

“Safety and care is our utmost concern.” Reid assured, adding, “Thankfully temperatures have dipped back into the normal range for Virginia.” Phew!