Trees not easily recovering from drought

Oct. 2—A trip up north highlighted the hardships the two-year drought has left behind.

In Mankato the Minnesota River at Sibley Park is a web of sand bars and the Blue Earth River is nearly just a trickle.

While the corn and soybean crops look fairly good in the counties just north of here, thanks to a few timely rains early in the season, the stress of long stretches of heat and little rain is cutting into yields as farmers begin combining beans.

Lawns and gardens are parched and browning.

Farther north, near Hutchinson and up to St. Cloud, corn is stunted in the dry sandy soil.

In the tree-dominated Brainerd Lakes area, it's the trees that are showing the stress and long-term damage.

Pine trees of all kinds have yellow-brown patches among the needles and the deciduous trees are losing their leaves early. The drought is likely to dull the fall color show in many parts of the state.

While stressed crops and lawns are a product of this summer's dry conditions, the trees are suffering from the severe drought that hit last year and the parched, hot conditions that continued in many places this summer.

The Star Tribune reports the Twin Cities saw its longest recorded streak of days that reached 70 degrees or hotter this summer.

The 118-day stretch, from May 27 to Sept. 21, beat out the previous length of 107 days set in 2018, according to the National Weather Service office in Chanhassen.

Even some metro area homes have been damaged by the long-term drought. As the dry soil shrinks, cracks begin to appear in foundations and on interior walls.

But it is the trees that are most showing damage. Oak trees are taking a pummeling. The Department of Natural Resources says it takes two to four years for trees to recover from long droughts, but the oaks become more susceptible to attack from insects and diseases. Oak wilt — a deadly disease that affects all species of oaks — may be the most worrisome for Minnesotans.

But pines, including Minnesota's state tree, the red pine, have a precarious future as the long-term climate becomes harsher.

The only bright spot is that forests appear to know that more young drought-resistant trees are needed. Ecologist Suzanne Simard discovered that trees use underground fungi networks to communicate and share resources, which runs counter to the idea that nature constantly competes for survival.

Studies by other researchers are showing that, somehow, that interconnected network is allowing non-drought-resistant seedlings to die off while the network nourishes young drought-resistant trees.

Beyond being a fascinating discovery, it shows us again how little we really know about the world around us.

Tim Krohn can be contacted at or 507-720-1300.