When the Forest Runs Dry — Preparing for a Future of Drought

At SLU, PhD student Emily Viola Delin studies how forests respond to prolonged dry periods and what that means for Sweden’s preparedness in a changing climate. Her work focuses on modeling abiotic disturbances — storms, fires, and especially droughts — to understand how management choices can make forests more resilient to the stresses ahead.

“Drought is sometimes called a slow crisis,” Emily explains. “It develops gradually and often goes unnoticed until the effects are widespread. By the time we see visible signs in forests, the underlying stress has already been building for a long time — which makes early monitoring and preparedness essential.”

What happens when the forest dries out

At the Asa Experimental Forest in southern Sweden, Emily and her colleagues are combining long-term data on soil moisture, tree rings, and water flows to understand how drought shapes forests over decades.

“We’re still in the early stages,” she says, “but this unique data helps us see how drought affects growth, recovery, and water balance over time.”

Even when trees survive, they often emerge weaker — less able to withstand new pressures from storms, pests, or fire. “Forest stressors rarely occur in isolation,” Emily notes. “They interact and amplify each other’s effects. A drought doesn’t just end when it rains again — it leaves a mark that makes the next disturbance harder to face.”

Unlike wildfires or storms, drought isn’t something that can be contained or fought in the moment. “It develops quietly, over weeks or months,” Emily says. “That’s what makes monitoring and proactive planning so critical.”

Preparedness rooted in resilience

For Emily, preparedness isn’t just about response — it’s about resilience.
“Forests teach us that recovery and maintaining function after disturbance are just as important as handling the event itself,” she explains.

By monitoring how often and how severely forests experience drought stress, scientists can identify early warning signals of broader water shortages that could also affect people and agriculture. “Forests don’t have irrigation systems — they show us where the limits are before those limits reach us,” she says.

The challenge, she adds, lies in balancing competing water needs among people, ecosystems, and industries. “As droughts become more frequent and severe, we’ll need clearer, coordinated plans for how to conserve and distribute water. It’s not just a forest issue — it’s a societal one.”

Adapting Like Nature

When forests face drought, they adapt by conserving energy — slowing growth above ground and expanding roots in search of moisture.
“It’s a lesson in resourcefulness,” Emily says. “We can learn from that by being more deliberate about how we use and prioritize our own resources — especially during and between crises.”

As droughts and water stress become more frequent, preparedness will depend on how well we adapt.

“The actions we take now will determine how resilient we are later,” Emily says. “The forests of the future may look different, but that’s part of their strength. Both people and trees have an incredible capacity to adapt — we just need the knowledge and will to guide that process.”