It has been said it is inevitable the emerald ash borer (EAB) will destroy all the ash trees in the country, but Indiana’s Department of Natural Resources (DNR) is not taking this challenge lying down. At least some ash trees in Indiana will survive the EAB invasion, if a DNR initiative is successful.

 

The agency is using chemical treatments to protect large specimens of ash trees in areas unaffected so far by EAB. The project includes trees in Turkey Run State Park and several nature preserves.

 

“We are hoping to save these awe-inspiring monarchs of the forest for everyone to continue to enjoy,” said John Bacone, director of the DNR Division of Nature Preserves.

 

 Candidate trees were identified and tagged by staff from Nature Preserves. Treatments will take place this spring and will include at least a few specimens of all ash species found in Indiana: white, black, blue, green and pumpkin ash.

 

EAB is a non-native insect killing almost all of the mature ash trees in the northern two-thirds of Indiana. The invasion is advancing south. Without intervention, all ash trees in the state will likely die.

 

Saving ashes from EAB will require commitment. They must be treated every 2-3 years. Once the EAB “killing wave” passes through and most ash trees are gone, treatments may not need to be as frequent.

 

The reasons for saving at least some large ash trees are several, according to Phil Marshall, forest pest specialist with DNR divisions of Forestry and Entomology & Plant Pathology. One of the most important is the female ash trees saved can serve as a seed source for EAB-resistant ash breeding efforts.

 

Some hope the breeding efforts, combined with potential developments to keep EAB populations in check, may  lead to the reestablishment of ash trees throughout its range. For some, just the chance to see the large trees in years to come is reason enough.

 

“The big ash trees that one sees when walking the trails at Turkey Run State Park and Big Walnut Nature Preserve are inspiring, and we hope we can help them remain there going forward,” Bacone said.

 

Mild weather could benefit fish and fishing

 

If the mild winter weather this year carries over through spring and summer, fish populations in northeastern Indiana lakes could benefit.

 

DNR biologists say weather has a big impact on lake temperatures, oxygen levels and water clarity – key factors determining how much habitat is available for fish.

 

“Our data show that more habitat and better habitat is present when overall conditions are warmer and drier,” said Jed Pearson, DNR fisheries biologist.

 

“Less habitat is present in colder, wetter years.”

 

Habitat includes the space fish have to swim and forage in, and areas where temperature and oxygen are more to their liking. Based on a nine-year study of summer habitat conditions at Crooked Lake, north of Columbia City, the depth where fish can live varies as much as 30 percent from year to year.

 

In an average year, suitable habitat extends from the surface down to 24 feet.

 

Below 24 feet, oxygen levels drop too low for fish to breathe.

 

During 2012, a warm and dry year, habitat was present down to 28 feet. In contrast, fish were confined to the top 21 feet of water in 2014, a cool, wet year. “These variations can also affect where fishermen find fish,” Pearson said.

 

Each summer, most area lakes stratify into three layers: a surface warm-water layer, a middle cool-water layer and a bottom cold-water layer. Water is a great insulator, so once the layers set up in spring they usually persist through summer. Oxygen levels, however, can vary within the layers depending on the amount of sunlight, water clarity and abundance of aquatic plants.

 

At Crooked Lake, the warm-water layer typically extends from the surface down to 18 feet. This is where anglers usually catch bluegill and bass. Plenty of oxygen is always available.

 

The cool-water layer is narrower and sets up between 18-20 feet, where water temperatures range from 68-73 degrees, which is where perch typically hang out.

 

The bottom habitat layer usually sits between 20-24 feet deep. It is where the lake’s ciscoes, a native fish species related to trout, can be found.

 

The cold-water layer at Crooked Lake was thickest in 2010, 2012 and 2016 but virtually disappeared in 2014. In some years, as conditions deteriorate, Cisco die-offs have occurred when the fish were unable to find cold water with enough oxygen.

 

In addition to studying habitat at Crooked Lake, Pearson is looking at data from two other lakes: Adams Lake in LaGrange County and Waubee Lake in Kosciusko County.

 

“We’re seeing the same sort of variation in each,” he said. “All three lakes had more habitat in 2012, the warm, dry year, and less habitat in 2014, the cold, wet year. All three followed a similar pattern in other years.”

 

So, if the warm weather conditions continue, barring any continued heavy rains, 2017 could be a very good year for fish – and fishing.

 

The views and opinions expressed in this column are those of the author and not necessarily those of Farm World. Readers with questions or comments may contact Jack Spaulding by e-mail at jackspaulding@hughes.net or by writing to him in care of this publication.