Thursday, November 29, 2012

Tree Planting Studies

Led by Graham Herbst, Community Forester based in Omaha, the Nebraska Forest Service recently implemented two tree planting studies to evaluate and help determine best growing and planting methods for better tree health in the landscape. The first study involved the planting of Swamp White Oak trees at Dodge Park in Omaha. Dodge Park is situated along the Missouri River and was heavily impacted by flooding in 2011. Swamp white oak was chosen to better tolerate any potential future flooding. The study includes trees grown by four different nursery methods: traditional plastic containers, Rootmaker(TM) grow bags (root trapper), balled and burlapped (B&B), and small seedlings started in square containers (Anderson pots). Trees were planted at proper depth and to try and simulate typical homeowner planting methods, so no extra care was given to root handling.  All trees will be monitored over time for growth rate and their root systems will be excavated by air spade in 5 and 10 years to evaluate root growth/health.


Planting locations at Dodge Park in Omaha

Tree grown in root trapper grow bag.

Tree grown in traditional container.


A second study was installed on UNL's East Campus in Lincoln. Part of the study includes evaluation of three nursery growing methods for Autumn Blaze Maple: B&B, traditional container and grow-bags. A second part of the study is designed to evaluate planting depth on tree health. Ornamental plum trees grown in grow bags were planted at varying depths ranging from 4" above grade to 12" below grade. All trees will be monitored for growth rate and their root systems will be excavated by air-spade in future years to evaluate root impacts.
Karma Larsen instructs Kendall Weyers to "dig over there."
 
Autumn Blaze Maple - B&B planting evaluation.
 
Finished planting of plum trees for depth study.

Sunday, November 11, 2012

Doing Battle with Cedars (to benefit oaks)

In the southeast corner of Nebraska, near the little town of Salem (a stone's throw from the Kansas border) grows a unique population of oaks known as dwarf chinkapin oak. Depending on the type of soil they grow in, this close cousin of the chinkapin oak (Quercus muehlenbergii), can grow as small, multi-stem trees or as sprawling shrubs, resembling American plum. This population of oaks is known far and wide by oak aficionados and is home to the national champion of the species!  The Nebraska Statewide Arboretum collects acorns from these plants nearly every year for nursery production as there is growing interest across the country for use of this species in the landscape. It is especially favored by wildlife enthusiasts. Most of the Salem population is found on dryer, rocky knobs, growing in association with relatively diverse mixed-grass prairie. The surrounding area is also home to some of Nebraska's most diverse deciduous forestland including hickories, redbuds, red oaks and many old and mighty bur oaks.
 
Oxymoronic: a large dwarf chinkapin oak (Quercus prinoides).
A plant this size may be a hundred years old or older!
Unfortunately, in recent years this area has seen an explosion in the growth of eastern redcedar, which are starting to choke out many of these unique oaks. Something needed to be done and recently a few of us from the Nebraska Forest Service spent a day on the property cutting out cedars. Armed with many chainsaws (and other saws) we happily cut and destroyed as many cedars as we could. We think we killed about 1,500. Many more still need to come out and we look forward to returning next year to continue the assault.
Cutting out eastern redcedars (Juniperus virginiana)

The Cutting Crew

 
 The beautiful day ended with a delicious chili and cornbread lunch prepared by the Stalder Family, long-time residents of the area and owners of the unique woodlands. A good time was had by all.
Mmmm. Chili and cornbread at the Stalder Farmstead.