Why Hurricane Florence's arrival could topple trees, ruin crops in the Baltimore region

Erik Dihle, Baltimore city arborist, discusses the risk of trees toppling due to ground saturation. (Amy Davis, Baltimore Sun video)

Persistent rain in the last couple of weeks — and throughout the summer — has has turned the ground throughout the Baltimore region into a soft, wet mess, toppling the occasional tree as happened this past weekend on St. Paul Street and University Avenue in the city.

More bad weather — particularly with high winds from Hurricane Florence — could send end more trees crashing down and ruin crops.


About 3 inches of rain have fallen in Baltimore since the beginning of September, enough to further saturate ground already holding a lot of water from a rainy summer and cause sporadic flooding. The National Weather Service predicts more rain this week, probably a lot more, and it will only take a bit of wind to create damaging conditions.

Isha Renta, a National Weather Service meteorologist, noted that Florence, which is expected to make landfall on the East Coast Thursday evening or Friday morning, could bring a wave of danger.


Hurricane Florence is threatening to strike the East Coast as a Category 5 hurricane, prompting calls for evacuation in the Carolinas and an emergency declaration in Maryland ahead of potentially "historic" flooding.

“The wind could knock down trees and the flood could ruin crops, but it all depends on the track of the hurricane and how far away it is,” Renta said. “It’s hard to tell just yet how much of a concern it is.”

Maryland Gov. Larry Hogan already declared a State of Emergency, as have governors in Virginia and the Carolinas, where some evacuations have been ordered.

Erik Dihle, an arborist with the Baltimore Department of Recreation and Parks, said the city has lost few trees so far due to heavy rainfall. There are 2.6 million trees in Baltimore, including 135,000 along streets. In the past month and a half of rain, fewer than 100 that have fallen down.

He said major storms in past years have cleared some of the damaged and diseased trees that did not have strong root systems to anchor them.

Hurricane Florence is forecast to hit the Southeast coast as a major storm later this week. What could it bring to Maryland? Strong winds, heavy rain and flooding and/or storm surge, depending on its track.

Further, the city has been proactively going neighborhood to neighborhood to trim the larger branches getting too close to buildings and cut down trees that could fall and pose a threat, Dihle said. The city is tackling 10 to 17 neighborhoods a year, he said.

But, he said, residents should report trees that are downed on power lines to the power company. For trees on public property, residents should alert government officials if a tree is suddenly leaning or there is a visible hump of soil where roots may be coming up. Trees on private property are the property owners’ responsibility.

“We remain on alert because the ground is saturated,” Dihle said. “More trees could be susceptible and the public should be on alert too.”

Generally, he said, all the rain has been good for gardens and trees, with roots growing deeper and stronger. So, residents shouldn’t be too concerned if they have shade trees near their houses.

A map of Maryland flood zones, created earlier this year, shows residents when to evacuate.

“Consider the benefits they provide versus the low level of risk,” he said. “They lower our utility bills, scour the air and water of pollution. ...They give us a better quality of life.”

Farmers, however, remain highly concerned about flooding. Floods could ruin crops such as soy beans and corn, which are planted on just over half of the 2.2 million acres in the state zoned for agriculture and are used largely to feed chickens, said Colby Ferguson, director of government relations for the Maryland Farm Bureau. The rest of the agricultural land is used as animal pasture and fields or to grow fruits and vegetables for people.

The ground is soaked already in many parts of the state and the rain expected over the next few days could spill streams and rivers over their banks, he said. Flash flooding also could take out fencing required to keep cows away from the waterways, which would require farmers to corral them in barns or other places, he said. Farmers then would have to find the animals food because they wouldn’t be in the pastures.

Flooding in April and again in July already has strained the state’s farmers, Ferguson said. Farmers in 11 states received federal aid after the April floods, he said.


Ferguson said high winds also could easily topple tall, mature corn stalks, but that may be less of a risk since the hurricane isn’t likely to hit the state directly.

“Flooding is the biggest issue we’d have because it’s already so wet and streams already are at their limits and the ground is already saturated,” he said. “There isn’t a lot of absorption.”

There is one crop, though, that is largely benefiting from all the rain: Christmas trees.

Robert Ruhl, of Ruhl’s Tree Farm in Phoenix, said his trees are doing well. They won’t be harmed even if the hurricane comes through, unlike other farmed crops such as corn and soybeans.

“Rain is good for them, and they won’t be affected even in a hurricane because they are in a field by themselves,” he said. “They aren’t big enough to blow over. ...There’s grass in between them and they and drain well. They will be fine.”

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