Forester tracks health threats to national forestlands

By Don Ingle

The Northcountry Sportsman

BALDWIN – Something out there is eating our forests – make that “things.” There are more than a few tree invaders at work destroying our woodlands.

One man who knows these threats well is Matt Sands, silvaculturist for the Manistee National Forest. That title’s a big word; it’s becoming an increasingly big job.

Sands’ job is to monitor the health and growing conditions for the Huron-Manistee National Forest. These days a big part of that is the tracking of insect and plant diseases, foreign and domestic, that continue to threaten the health of these national forestlands.

Asked in an earlier interview to list the top forest insect/disease threats today, he still puts the “Emerald ash borer” (EAB) as number one. But there is now another and growing threat that ranks as high on his list of most damaging impacts and that is “Oak decline.”

Since much of this region’s forest cover is in oaks, people should be aware of the symptoms of oak decline. “Recent inspections of the region’s oaks show that this continues to be a growing problem in West and Northwest Michigan,” he noted.

Sands described the way a landowner can detect this disease. “The leaves turn to a bronze color, usually starting at the top. But then in about 1-2 weeks the leaves begin to drop. Unfortunately when that’s seen, the tree is dead. Once the symptoms appear, it is already too late.”

(Those who drive east from Ludington to Baldwin will note the number of dead or dying oaks in the woodlands near the highway.) That, Sands said, is an example of the impact of oak decline. It is a combination of old age and insect and fungus disease and may also be spread to other oaks through their root systems.

“Several thousand acres are known to have Oak decline in Michigan, and it’s just one of many threats by insects or fungal diseases that are impacting the forest’s health.”

Some impacts are caused by native diseases or insects, but more and more there are new foreign causes being seen – a result of our being in a world economy.

Imports from other parts of the world bring in more than just manufactured products, Sands notes. “Imports also bring in insects and diseases for which forests have no natural defense.” Just as ballast water discharges into the Great Lakes have brought in aquatic invaders, “pallet wood and packaging materials have carried foreign insects and fungal diseases that have impacted on our woodlands.”

In fact, it is not just a modern-day problem. The Dutch elm disease was an early-on example of this, and the once-common American elm tree was severely hit, even decimated by the disease in many areas. Today’s new imported threats are doing the same for many of our other native forest species. Similarly, the Chestnut Blight has extirpated our Native American Chestnut trees, once one of the more common trees of our eastern forests.

Sands named several other health problems that pose current threats. Among these is Beech Bark disease. “This results from a two-hit punch made by a white scale that causes wounds on the trunk. A second blow follows as the wound allows a fungal invasion through the cambium layer, causing weakness to the tree.”

“Infected trees may break off limbs and split, even causing potential danger to people. Such a danger caused closure of campgrounds in several areas of West Michigan. It also impacted wildlife which depends on the mast crop of nuts on the beech trees there, and also in most West Michigan counties. It’s spread by birds and also by moving infected firewood,” Sands explained.

He noted the foreign threats get in from cargo pallets from foreign shipping. The insects or the other diseases are in the pallet wood used to load imported goods. “That is how the emerald ash borer got in. The damages caused by this invasive beetle have made ash trees in Michigan’s forests close to being extirpated.”

Sands notes that seeds from the ash are being collected and stored for possible reintroduction at a later time when the EAB has eaten the last of our native ash trees. Once it has no ash to feed on, the insect will die off. But recovery then is likely to be for a future generations to know.

“We also have native diseases to worry about - the Forest Tent Caterpillar can be a big problem. There have been several thousand acres defoliated in Wexford County.” After several years of defoliation the host tree may weaken and die off.

Spruce and Jack pine budworm are problems in some areas. Other native threats at least have some native controls; but the real worry comes from the foreign invaders for which no local natural protection is known.

Silvaculturists like Sands have recently become concerned over the Asian Longhorned Beetle. “It has been very hard on maple. Massachusetts forests have been hit hard, and there are drastic measures being taken to control it. There are also incidents in Chicago and New York City.” Not yet known to be in Michigan, it is a threat to Michigan’s important maple forests so it is being monitored closely.

“As long as we continue to be involved in world trade and product importation, we will face threats to our forests. Finding them and taking whatever quick action is possible will require a constant monitoring of our valuable woodlands.”

Silvaculturists like Matt Sands are at the front line in the constant battle to keep our forests healthy and growing in the face of each new foreign or domestic insect threat.