Tuesday, February 25, 2014

An Evergreen for Tight Spaces

Hardiness of Redcedar Takes on Elegant Form in Taylor Juniper

Near the town of Taylor in central Nebraska, a unique variation of eastern redcedar was discovered in 1978. It’s a narrow, very upright tree growing to 25' tall and just 3' wide, not at all the irregular shape of most redcedars.
        It looks like it belongs in a formal French garden rather than a prairie but it’s as disease-resistant and tolerant of a wide variety of soil and environmental conditions as common redcedar. With a mass of native grass at its feet, it’s at home in the country, but it has proven hardy in tough urban sites such as narrow planting beds next to brick walls and concrete. It even offers the bonus of beautiful silvery-blue juniper berries.
        Long-lived groupings of Taylor junipers can be found in several places throughout the University of Nebraska-Lincoln campus. With such a narrow, vertical form it needs to be carefully integrated into a landscape design but in the right places, it can soften urban landscapes and provide year-round green in narrow spaces around tall buildings.
Taylor Junipers at Lincoln's Pioneers Park and the state capitol

Tuesday, February 18, 2014

Gardens from the Inside out

Tips and Excerpts from “Outside the Not So Big House” by Julie Moir Messervy, landscape architect, and Sarah Susanka, author of “The Not So Big House”

Winter is a good time to evaluate the connection between the house and the yard. Certainly pathways become far more important in getting from one place to another. And, for those of us who love being outdoors, windows and connecting structures like hallways, patios and arbors play a much more valuable role in bringing the outdoors in. 
       The book “The Not So Big House” aimed at better use and expansion of small spaces. In “Outside the Not So Big House”, Susanka worked with landscape architect Julie Moir Messervy to carry that a step further—into the landscape surrounding our homes. Here’s a few suggestions and excerpts:
  • “Framed openings, such as windows and doors, help you to establish a visual link between inside and out. In addition, building transitional spaces, like decks, porches or balconies, makes the space between building and landscape more accessible.”
  • Using local plants and hardscape materials, ties the home landscape to the larger, natural landscape, besides being environmentally smart in many other ways (use local!).
  • Borrow the landscape to expand the sense of space--from neighbors, long distance views, etc.
  • Corners within homes and other buildings are important—they make us feel sheltered, comfortable, nestled (they’re always the most sought-after tables in a restaurant). Corners with a view are even more appealing.
  • Repeating forms and materials is one of the best way to tie the inside to the outside—colors, stones, geometric patterns, even the same plants.
  • “Vertical shapes demand our attention, whereas long, horizontal shapes feel restful to the eye.”
  • “When a window or doorway is aligned with an important feature in the surrounding landscape, there’s a powerful sense of order and balance.”

Monday, February 10, 2014

Caring for Storm-damaged Trees

 Nebraska Forest Service, Community Forestry & Sustainable Landscapes staff

Trees damaged by storms generally require some degree of immediate attention (removal of low hanging branches, clearance from utility lines, etc). Homeowners working on their trees need to be careful to watch out for safety concerns and to consider the best approach for dealing with the tree they are trying to save. Chain saw work off the ground and other heavy work (essentially all work on large trees) should be done only by professional arborists.
        Hazardous Trees. Loose or loosely attached branches and split trunks are obvious safety concerns that should be taken care of as soon as possible to avoid the possibility of injuring someone or damaging property later when the branch or that part of the tree falls. Broken but firmly attached branches that pose no immediate danger of falling can be pruned whenever convenient after the more hazardous loose branches have been removed. Trunks split down the middle are very difficult to brace adequately, and trees with split trunks should be removed or taken care of by a professional arborist.
        Power Lines.  Branches hanging over, or near, power lines are a major safety hazard from any standpoint. Special training is required to prune branches near power lines safely. Homeowners should never attempt to prune these branches themselves. Contact your local power company or an arborist trained in electrical line clearance to have these branches removed.
        Leaning Trees.  The heavy weight of snow or ice may tip a tree over by breaking some of the roots. Trees leaning from root breakage usually do not survive well. If a tree tips or develops a permanent lean in a storm, it often means the tree had damaged or poorly developed roots before the storm pushed it over. If a leaning tree does survive, it often becomes a hazard from the damage it could cause if it were to fall. Mature trees rarely survive attempts to pull them back into place after being tipped over by a storm. These generally should be removed and replaced with new trees. Very young trees (typically less than 10 years in the ground) may survive if the trees are gently pulled back to their vertical positions. If this is done, avoid additional damage to the remaining roots if possible, press out any air spaces that may have formed in the loosened soil, water the area of the root system twice each week in the absence of rain during the fall, spring, and summer, cover the root area with two to four inches of wood chip mulch, and stake the tree for the first year to prevent the tree from falling again. Do not use rope, wire, wire in garden hose, or any narrow band of material to tie around the tree during the growing season. These will injure the trunk and could kill the tree as it tries to grow. Use a broad strap or other fabric at least one inch wide and inspect and adjust the location of the strap once each week during the growing season to minimize any injury the strap might cause to the bark.
        Pruning.  The only pruning that should be done at this time is the removal of broken branches. Leave the fine pruning and finishing cuts until later. All pruning cuts will dry out to some degree during the winter. Take care not to leave any stubs from your pruning cuts as these will not allow the tree to heal properly.  Have a trained arborist make the final pruning cuts, especially on larger mature trees. Branches that have pulled away from the trunk should be removed at the bottom of the split. Avoid causing any additional damage to the trunk. Remove any loose bark or wood fibers, but do not cut into bark that is living and still attached. Never top trees, topping creates serious hazards and dramatically shortens the life of a tree.  And never use paint or wound dressing to cover wounds. These materials do no good for the tree and actually interfere with the tree's wound sealing process.
        Be Conservative.  Do not prune or remove more than you have to at this time. Remove hazards, but save other decisions on pruning and removals for later. While the damage may look severe at this time, concentrate more on how to can save trees rather than making quick decisions on cutting them down. Keep in mind why you wanted your trees. The trees may still be able to serve that function. Don't be too hasty to make a decision to remove a tree if you can delay that decision to the spring or even a year from now. You may decide later the tree was not damaged as badly as you thought.
        For more information, go to: http://www.nfs.unl.edu/ or http://arboretum.unl.edu/. A whole series on storm damage can be found at: http://nfs.unl.edu/documents/communityforestry/Storm%20Damage%20series%20entire.pdf.

Tuesday, February 4, 2014

Restless about Natives

Written by Jim Locklear

        It’s hard to imagine that there could be controversy surrounding something like gardening, but an ongoing, heated debate over the issue of using native vs. non-native plants occasionally rears its head, even in Nebraska.

        Dr. Michael Dirr, noted authority on woody landscape plants, has written of his fellow horticulturists, “Friendships are solidified and shattered over native plants.”
        The battle lines are usually drawn by folks who, for a number of different reasons, feel that native plants are the best choice for use in our cultivated landscapes.  Most native plant enthusiasts are content to simply inspire wider use of natives; others, however, are more adamant and take a more activist approach.
        While these things will continue to be debated in the pages of horticultural and environmental publications, the average person just wants to know what’s the best plant for their landscape.
        A native plant is one that occurs or occurred naturally in a particular region.  Sometimes this definition is tightened up by tacking on the phrase, “before European settlement.”  The key, however, is how you define the region.
        The boundaries of the region in question are most often man-made, such as a political unit.  However, the fact that a plant is native to a particular state, like Nebraska, is not necessarily an indication of how well it will perform as a landscape plant across the state.
        Limber pine, for example, occurs in Nebraska, but only in one small population west of Kimball near the Wyoming line.  White oak just makes it into Nebraska in the southeast corner of the state.  While both are natives, they have extremely limited distributions at opposite ends of Nebraska, and do not always perform as well outside of their ranges.
        Some plants may be widespread, and quite hardy, but are not appealing as landscape plants.  An example is box elder, a smaller tree that occurs across Nebraska but which lacks much ornamental value and therefore is not often grown as a landscape plant (one horticultural writer labeled it an “alley cat” tree).
        The great advantage of natives is that they are well adapted to local growing conditions and should, therefore, require less water, fertilizer, pesticides, etc. to grow and maintain.  There is also less chance of natives becoming invasive weeds, since their natural competitors are present locally.
        A less practical, but equally valid reason for the use of natives is that they reflect a sense of the natural landscape of the region, a sense of place.  Many people are tired of landscapes that look like every other place in the country.  Using natives allows them to bring a regional character to their surroundings.
        No plant, native or non-native, is without its limitations.  Bur oak is a magnificent tree, but relatively slow growing.  Green ash is very hardy, but suffers from borer insects.  Sycamores have beautiful bark, but may grow too large for most urban landscapes.
        The most important issue in selecting plants (assuming they are non-invasive) is not whether they are native, but whether they are well adapted to the growing conditions they will face in the landscape.  Few people would observe bald cypress in its natural setting in a southern swamp and imagine it would grow in Nebraska.  Yet this non-native has proven to be a hardy, adaptable tree in Nebraska that can tolerate both wet and dry conditions.