Dakota Gardener: Data driven

Math is important.

It's tough, though, trying to teach that to students who study natural resources management. Most people go into the broader field of natural resources because they love the outdoors – hiking, camping, fishing, hunting.

But these people often aren't into math. They don't want to add, multiply and use statistics to make estimates.

The older students do a lot better with these concepts than the younger ones do.

My advisor in graduate school had a saying, "You can't manage it, if you can't measure it." There's a lot of truth in that statement, especially for those who manage ecosystems like forests.

In North Dakota, one type of forest that people manage is the urban forests of our communities. Urban forests provide critical green infrastructure in our towns and cities, offering shade, wind protection and a number of "ecosystem services" like stormwater reduction and wildlife habitat.

How many trees are in your town? How big are they? What species are they? Has anyone even determined this information for your town?

For more than 100 of our smaller communities, the answer is "yes." Over the past 15 years, personnel from the North Dakota Forest Service (NDFS) have completed inventories of the public trees – those on boulevards, parks and other public lands – for a number of towns. The information is available online through the ND Tip Tool at https://www.ndcitytrees.org/NorthDakota/.

It's a great resource.

Did you know that there were 557 public trees in Carson, N.D., at the time of their inventory? Just over 100 of them (19.2%) were green ash.

On average, the community forests of North Dakota have 37% green ash. For some communities, it's as high as 90%. When emerald ash borer arrives in those towns, the impact will be huge.

The TIP Tool also displays the size of each individual tree, shown as its diameter at breast height (DBH). Communities have the option of actively assisting with their tree inventory and managing their own data. The additional data includes the condition of each tree – basically, its health. Accessing this data requires a login credential and some training, available from NDFS Community Forestry Staff.

I don't know which town has the most diverse urban forest. Only a deep dive into the data will reveal that.

What I can tell you, though, is that Carson has 30 tree species represented on its boulevards and in the parks. One of those trees is a northern catalpa, a unique species that we don't often see in North Dakota communities. I love its clusters of white flowers in the spring, along with its enormous leaves. It needs a little extra irrigation, though, in our drier prairie environment.

Crosby, N.D., has 34 tree species, but more than 2,300 public trees. That doesn't include trees found in yards on private property. There are likely some additional, really unique species mixed in there as well.

If you can't measure it, you can't manage it. But for many communities, the forest has been measured, and now those managers can make informed decisions. Data driven.

Do you know how many trees – especially ash trees – are in your town?