Four techniques for compaction amelioration were studied: 1) Vertical drainage panels; 2) vertical gravel-filled sump drains; 3) soil trenches filled with sandy loam; and 4) peat amended back fill. The control was backfilled with existing soil on the site. Vertical drainage mats and vertical gravel-filled sump drains were shown to increase O2% in surrounding soil; however, all O2 levels regardless of treatment were above what is considered limiting. Shoot and root growth of Pyrus calleryana `Redspire' was greatest for treatments that alleviated mechanical impedance (soil trenches and amended back fill) and least for treatments that did not (controls and vertical drains). Vertical drainage mats which alleviated mechanical impedance to a lesser degree showed intermediate growth.
Susan D. Day and Nina L. Bassuk
J. Roger Harris and Susan D. Day
Root flares of landscape trees are increasingly found to be much deeper than their forest counterparts, indicating that their root systems have been situated deeper in the soil. Planting deeply in production containers contributes to this phenomenon, yet the consequences of deep planting in production containers or the consequences of any adjustments made to planting depth at the time of transplant on growth in the landscape have not been reported for many species. Container-grown (11.4 L) liners of Tilia cordata Mill. (littleleaf linden) and Quercus palustris Münchh. (pin oak) were planted in 50-L containers with the first main lateral roots (structural roots) at substrate-surface grade or 10 cm or 20 cm below grade (deep planting). Trees were grown in the 50-L containers for two growing seasons and in a simulated landscape for three additional seasons after transplanting with the top of the container substrate at soil level or with some roots and substrate removed such that the original structural roots were just below the soil surface (remediated). Deep planting pin oak, but not littleleaf linden, slowed growth during container production; however, the effect did not persist after transplanting. Remediation of the 20-cm-deep pin oaks slowed growth during all three post-transplant years. Littleleaf linden remediation slowed growth for the first season after transplanting to a simulated landscape for 10-cm-deep trees and for the first two seasons for 20-cm-deep trees. Evaluation of pin oak root systems 3 years after transplanting revealed vigorous growth of non-deflected adventitious roots that had formed on the trunks of deep trees, and these roots appeared to be developing into main structural roots. No adventitious roots were present on littleleaf linden; instead, deflected roots grew and produced deformed root systems. Deep planting of linden reduced suckering; however, we conclude that remediation of deep-planted littleleaf linden is warranted as a result of potential hazards from trunk-girdling roots. In some species such as pin oak, non-deflected, strong adventitious root systems may assume the role of structural roots and diminish the effect of deflected and circling roots systems formed during container production. Remediation of these trees is likely not as critical as for species without abundant adventitious roots.
Susan D. Day, Paula Diane Relf, and Marc T. Aveni
A multi-faceted extension education program to reduce consumer contributions to nonpoint source pollution by encouraging proper landscape management was initiated in Prince William County, Va., and funded through the USDA-extension service. The program now is being replicated in several counties in Virginia, primarily in the Chesapeake Bay watershed. The program recruits participants through educational field days, advertisement and other means. Educational techniques include one-on-one assistance from Master Gardener volunteers and the use of Extension publications developed for this program. Publications developed include The Virginia Gardener Easy Reference to Sustainable Landscape Management and Water Quality Protection—a concise reference of Virginia Cooperative Extension landscaping recommendations that includes a calendar for recording fertilizer and pesticide applications, IPM, and other maintenance activities. The Virginia Gardener Guide to Water-wise Landscaping, was recently added to supplement the program in the area of water conservation. In Prince William County, over 700 people have participated. Most of those who complete the program report being more satisfied with their lawn appearance and spending less money. Participation also resulted in consumers being more likely to seek soil test information before applying fertilizer. Other effects include greater participation in leaf composting and grass clipping recycling and greater awareness of nonpoint source pollution.
Susan D. Day, Sheri T. Dorn, Diane Relf, and J. Roger Harris
Virginia Cooperative Extension's (VCE) Master Gardener!Tree Steward program (MGTS) provides advanced training in leadership development and arboriculture to Master Gardener (MG) volunteer educators so that they may expand the influence of extension through leadership in community forestry. According to a statewide survey, 70% of VCE MGs and agents with MG programs would like to be involved in community tree programming. Only 26% were currently involved. Typically, agents cite limited staff and volunteer resources as the primary factors in restricting program expansion. Furthermore, 90% of municipal foresters indicated they would like to work with trained volunteers. The MGTS program simultaneously answers the desire of MGs to expand their role in the community landscape and the need of VCE to expand its outreach with increasingly limited resources. MGTS training, guided by a 10-unit resource book, integrates technical and program management expertise to foster volunteer pride and self-sufficiency. This allows MGTSs to coordinate much of their own training and recruit and manage large numbers of non-MG volunteers to whom they can provide limited training for specific projects, thus, allowing program expansion without additional staff.
Susan D. Day, Sheri T. Dorn, Diane Relf, and J. Roger Harris
The Virginia Cooperative Extension (VCE) Advanced Master Gardener-Tree Steward (AMGTS) program provides advanced training in leadership development and arboriculture to MG volunteer educators so they may expand the influence of extension through leadership in community forestry. A statewide survey of agents, MGs, and foresters served as the basis for developing the training package, which was funded in part by the Virginia Department of Forestry. According to a statewide survey, 70% of VCE MGs and extension agents with MG programs would like to be involved in community tree programming, while only 26% was currently involved. Typically, agents cited limited staff and volunteer resources as the primary factors in restricting program expansion. Furthermore, 90% of municipal foresters indicated they would like to work with trained volunteers. The AMGTS program simultaneously answers the desire of MGs to expand their role in the community landscape and the need of VCE to expand its outreach with increasingly limited resources. AMGTS training, guided by a 10-unit resource book, integrates technical and program management expertise to foster volunteer pride and self-sufficiency. This allows MG tree stewards to coordinate much of their own training and recruit and manage non-MG volunteers to whom they can provide limited training for specific projects, thus allowing program expansion without additional staff. The training is designed for delivery by knowledgeable professionals in the local community, such as arborists, horticulturists, college professors, extension specialists, MGs, and others who can provide quality training following the program guidelines.
John D. Lea-Cox, Cindy Zhao, David S. Ross, Theodore E. Bilderback, J. Roger Harris, Susan D. Day, Chuanxue Hong, Thomas H. Yeager, Richard C. Beeson Jr, William L. Bauerle, Andrew G. Ristvey, Mary Lorscheider, Sarah Dickinson, and John M. Ruter
Increasing environmental concerns and legislation in many states and in other countries require that we take a more comprehensive sustainable “best management” approach to production techniques in nursery and greenhouse operations. This is particularly important because these production facilities are typically intense users of resources that are applied to relatively small land areas. We have developed an online knowledge center to facilitate the implementation of more sustainable practices within the nursery and greenhouse industry. A web-based knowledge center provides the most cost-effective mechanism for information delivery, as our potential audiences are extremely diverse and widespread. We currently have a registered user database of over 450 educators, growers, and industry professionals, and undergraduate and graduate students. A gateway website provides an overview of the issues and the goals of the project. The associated knowledge center currently has 25 in-depth learning modules, designed in a Moodle learning management framework. These learning modules are designed to actively engage learners in topics on substrate, irrigation, surface water, and nutrient and crop health management, which are integral to formulating farm-specific strategies for more sustainable water and nutrient management practices. Additional modules provide assessment and implementation tools for irrigation audits, irrigation methods and technologies, and water and nutrient management planning. The instructional design of the learning modules was paramount because there can be multiple strategies to improve site-specific production practices, which often require an integration of knowledge from engineering, plant science, and plant pathology disciplines. The assessment and review of current practices, and the decision to change a practice, are often not linear, nor simple. All modules were designed with this process in mind, and include numerous resources [pictures, diagrams, case studies, and assessment tools (e.g., spreadsheets and example calculations)] to enable the learner to fully understand all of the options available and to think critically about his/her decisions. Sixteen of the modules were used to teach an intensive 400-level “Principles of Water and Nutrient Management” course at the University of Maryland during Spring 2008 and 2009. The water and nutrient management planning module also supports the nursery and greenhouse Farmer Training Certification program in Maryland. The Maryland Department of Agriculture provides continuing education credits for all consultants and growers who register and complete any module in the knowledge center. Although these learning resources were developed by faculty in the eastern region of the United States, much of the information is applicable to more widespread audiences.