Outdoors Blog

Playing Outdoors mailbag: What’s happening at Horsethief, Hammer Flat?

Lynne Bachman expressed concern about the habitat-restoration efforts at Hammer Flat east of Boise. Idaho Fish and Game provided a lengthy, detailed explanation.
Lynne Bachman expressed concern about the habitat-restoration efforts at Hammer Flat east of Boise. Idaho Fish and Game provided a lengthy, detailed explanation. Special to the Idaho Statesman

As warranted, I’ll post a collection of reader questions with answers. Have a question? Email outdoors@idahostatesman.com.

Question: I know Horsethief Reservoir was drained this fall. What is happening there now? Fishing this summer, or not? — Scott Meissner

Answer: Idaho Fish and Game, which owns and operates the reservoir, drained it last fall to kill unwanted bullheads. Horsethief will be refilled this spring and stocked with rainbow trout (likely 12-inchers) and 6-inch brown trout. Fish and Game hopes to get a truck to the reservoir east of Cascade in early May.

Question: Do you have any information on what is happening up on Hammer Flat? We hiked there (Feb. 21) and there has been massive heavy equipment disturbance across the plateau. Any information would be helpful. Thanks! — Lynne Bachman

Answer: Idaho Fish and Game also owns Hammer Flat, a Boise Foothills plateau above the Black Cliffs east of the city. Hammer Flat was purchased from the city in 2011 to provide wildlife habitat and wildlife recreation opportunities. Wildlife habitat biologist Krista Muller of Fish and Game provided an in-depth response to Lynne.

“Hammer Flat was purchased by the Department of Fish and Game using funds from the Bonneville Power Administration and its partners to offset the loss of wildlife habitat as a result of construction of the Federal Columbia River Power System. The purchase was authorized by both agencies because the property provides critical winter range for migrating mule deer and elk, as well as a vast array of other wildlife species. As part of the agreement, a five-year Hammer Flat Improvement Plan was developed to increase habitat capacity through rehabilitation efforts. Habitat improvement efforts have been ongoing since 2012 and comprise of hand-planting, broadcast seeding and the use of mechanical equipment. All of our activities are authorized through a rigorous BPA process and are tracked for future reference. In addition, IDFG staff work closely with a variety of department biologists to minimize the effects these activities have on wildlife and desirable plants. Since the level of moisture is scarce on the property, these activities take place from November through March in order to allow both seed and seedlings time to establish properly before the dry summer is upon them.

“Bare root seedlings are planted on the property in two ways: 1) by hand planting and 2) by mechanical planting. The seedlings are hand-planted in areas not suited for mechanical methods (accessibility is difficult, there are rocky soils, steep hillsides and draws). With mechanical planting, a tree planter is pulled behind a tractor in order to create a slit in the soil. As the tractor moves forward, a rolling coulter cuts a slit in the ground approximately 1 to 2 inches wide and 2 to 3 inches deep. Moments later the trencher makes an opening in the soil no more than 10 inches wide and 12 inches deep, lifting the soil from the furrow upward and to the side. A person then removes a seedling from the rack on the tree planter and places it into the ground between the trencher blades. The person then holds the seedling in position until the forward motion of the planter causes the soil to fall back into the slit, holding the seedling in place. The packing wheels then force the furrow to close around the seedling and to pack the soil around it. The use of a tree planter will create neat, connecting rows of plants. Although this rehabilitation effort looks like it is creating a significant amount of soil disturbance, it actually minimizes the amount of competition from invasive weeds, creates a catch basin for spring rains and plants the seedlings at a depth for good root establishment.

“Broadcast seeding is conducted in areas not suited for mechanical methods. This technique is also conducted in areas that compliment hand and mechanical planting. With this approach, seeds are spread across the soil surface by hand throwing. Areas of seed distribution are selected where there is the least competition from invasive weeds or other plants. Broadcast seed density is approximately 250 cubic centimeters of seed (about a full 4-ounce plastic cup of seed) for each square meter.

“Finally, most of the rehabilitation activity that you notice out on Hammer Flat is from interseeding. Interseeding is a seeding technique that uses a machine to prepare a shallow seedbed and incorporates seed into the ground directly. Since the soils on Hammer Flat are so degraded by grazing and agriculture, and there is a significant lack of moisture, this is the most efficient and cost effective way to rehabilitate the property. This technique is used on the larger sections of the property with even terrain and is conducted using an implement called an interseeder. The implement is pulled behind a tractor while it prepares the shallow seedbed and sow seeds directly into the soil. The interseeder is a relatively simple fabricated toolbar that holds a three-point hitch assembly and the parking stand. The back toolbar holds three potato plows and the two gauge wheels. A 5x3-inch steel tube is mounted above the back toolbar to hold three hydraulically driven hopper boxes, each with a spout. The hopper boxes can be adjusted independently to regulate the flow of seed. Plastic hoses connect the spouts of the boxes to the solid seed pipe mounted behind each plow. Drag chains are attached at the bottom of the seed tube, just above the level of the seedbed. As the tractor moves forward, the plows cut three shallow furrows (24 inches apart) into the ground no more than 6 to 8 inches wide and 2 to 3 inches deep. Seconds later, seeds from the hopper are dropped into each of the furrows. A drag chain at the end of each seed tube then incorporates the seed into the ground and covers it with a layer of soil.

“All of these activities are conducted to increase the chance of survival of the seed and seedlings. It may take numerous attempts over the next several years to establish the amount of desirable plant and shrub species needed to support wildlife for the long term. Therefore, repeated seeding and planting will be conducted well into the future. Over time, the establishment of these plants and shrubs on the Boise River Wildlife Management Area will provide the critical forage big game need to survive the winter months. Furthermore, this vegetation will help hinder cheatgrass infestations, minimize fire damage and provide thermal cover and forage for a variety of other wildlife species including game birds.”

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