Farther along the trail, Ashton points to another wolf tree, a sugar maple that looms above the other trees in a field now half given over to saplings. The maple dates from a time when it stood in open farmland, which predominated in eastern Connecticut from about 1740 to 1850.

Pointing to the tree, Ashton says, “You’re looking at a legacy of successive transitions in land use. That’s an important culture tree. It’s also an important wildlife tree.” The wolf tree provides seeds for rodents to eat and a home for insects and for cavity-nesting birds and mammals.

Ashton explains that most of the trees here were cut for timber several years ago. The foresters spared the big maple, along with a few century-old trees that had grown in the abandoned agricultural field, leaving the trees to serve as sources of seeds and to shelter the young trees that would grow there after logging.

Camp tells the group: “When you’ve taken ‘stand dynamics,’ you’ll be able to pretty easily read forests like this.” Camp teaches Forest Dynamics: Growth and Development of Forest Stands, as well as courses in invasive species; Fire: Science and Policy; forest health; and alpine, arctic and boreal ecology.

Since understanding how significant change in a biological community—disturbance, in the parlance of foresters—provides a foundation for the study of ecology, Yale-Myers provides a useful laboratory. Ashton explains that big trees, like the maple, are more likely to withstand high winds, like those of the 1938 hurricane that hit the Connecticut coast at over 100 miles per hour. The hurricane damaged 20 percent of Yale’s 7,800-acre forest.

It’s time to work, and Ashton leads the students up a small hill thick with hickory, cherry, oak, paper birch, hemlock and ash. Here the students break into eight teams to begin their morning exercise—inventorying species of trees, their relative abundance, the sizes of trees and how much usable wood a section of forest contains.

Ashton walks by as a team is listing species in their plot. Amir Nadav and Simon Tudiver are curious to know what caused the death of a nearby hemlock, now brittle and black. Drought killed it, Ashton replies.

“Competition, competition. It’s sort of a sad story,” he says. “The rich get richer and the poor die. It’s very much how trees grow. As trees get bigger, they take up more space. Something has to give. You start with millions of seedlings. You end up with two trees.”

Meanwhile, Mira Manickam and Avery Anderson peer up the trunk of a very tall tree. Hickory? Ash? They can’t decide. “We learned our trees without any leaves on them. These pesky leaves are getting in the way,” says Anderson.

Now they are trying to identify the trees by the arrangement of their leaves on the stem. Ash leaves face one another, while hickory leaves are staggered. “Ash is opposite. Hickory is alternate,” Manickam murmurs.

In the afternoon, the group studies a freshwater stream for a lesson in estimating biodiversity. Squatting above the few inches of water left in the stream after a dry spell, Peter Christensen, who is studying for an environmental science degree, has caught two small fish and a lobster-like crayfish. He wants to find more evidence of diversity, but the net seems to be coming up empty. He decides to think small. “We need not to look for the celebrities like the crayfish and the minnows,” he jokes.

And then he manages to scoop up a small insect larva. He compares it to a laminated guide to aquatic life. “I love this,” he tells Eric Roberts. “This is to help us: ‘Looks like a small hellgrammite. ’” He and Roberts inspect the creature, comparing its filaments, mouth parts and legs to the drawings of larvae on the chart. They conclude that they’ve found a fishfly, from the order Megaloptera, which when mature is beige and has large globular eyes and triangular wings.

But as Esteban Rossi points out from his perch on a rock at the stream’s edge, the primary value of Mods is not so much that it teaches students to identify larvae, “It’s about getting to know the people while actually doing something. That’s really a good way to meet people. I think that’s the point—and it’s fun.”

Uromi Manage Goodale ’01, Ph. D. ’07, student, would have agreed with Rossi had she heard his comment, but she is back in the camp kitchen, marinating chicken in Biryani paste, grating coconut, squeezing limes and mixing together cumin, cardamom and cloves to spice rice. Word of her Indian-Sri Lankan feast has spread from one group to the other.

Goodale has more than good cuisine in mind as she watches over the stove: she designs her menus to affirm the varied origins of the students. Meals this summer included an American barbecue with corn on the cob and s’mores, Italian night with spaghetti and meatballs and bread pudding, sushi rice at breakfast and a Tex-Mex lunch. “If you think about all the things important to consider in terms of diversity,” she says, “food is very important.”

Recalling her experience attending Mods in 1999, Goodale says she was shocked and delighted when an American student approached and began chatting with her in Sinhala, Goodale’s native language. The student, Jennifer Grimm ’01, had served in the Peace Corps in Sri Lanka. With that conversation, Goodale’s view of the purpose of Mods changed abruptly.

“I came with the idea that we were going to study, and then I met all these people,” says Goodale. She discovered that fellow students were important for networking, brainstorming and sharing information—a rich resource at F&ES, she says, “on top of what we can get from books and classes and professors.”

“To have this connection with this group is really valuable,” she says. “It starts with Mods.”