Tree Planting Standards

 

Tree Planting Details & Specifications

 
 

 Studies:

  • Ruth S. Foster and Joan Blaine

    https://joa.isa-arbor.com/request.asp?JournalID=1&ArticleID=1485&Type=2

    Boston is an old city. It has parts that go back 300 years. Certain sections of the city have been residential and had trees for centuries-. It is possible to survey longevity because the age of the streets is older than the trees. Areas have been replanted a second and third time. This study deals only with sidewalk trees. Their survival rates and average age differ from trees in parks, parkways, and back and front yards.

  • Gilbertson & Bradshaw (1985)

    https://www.tandfonline.com/doi/abs/10.1080/03071375.1985.9746706

    The results of a survey of newly planted trees of eleven cities in the North of England are presented. The composition of the tree populations of these towns is seen to be dominated by a few species. The potential for growth is high, yet the average levels of shoot extension are remarkably poor. High levels of tree death are found in some towns. Water and nutrient stress are highlighted as major causes of the poor condition of urban trees. Vandalism and other causes of physical damage are much less important. It is argued from the evidence that much of the trouble must be attributed to the way techniques of planting and maintenance are applied in practice, rather than to any inherent problems of sites or trees in general.

  • Edward F. Gilman

    https://www.isa-arbor.com/Publications/Arboriculture-Urban-Forestry

    During the first and second year after transplanting into good soil, there was no apparent benefit from adding amendments to the backfill soil around newly planted 5 cm (2 in.) caliper live oaks (Quercus virginiana Mill.), nor was there a benefit from applying liquid additives over the root ball. Top growth in the first 2 years after planting was not enhanced on trees with amendments added to the backfill soil compared to the control. In the first growing season following planting, trees irrigated frequently (3 times per week for 38 weeks) grew about twice as fast as those irrigated only during the first 3 months after planting. There was no lingering effect of irrigation on top growth rates once irrigation ceased. Trunk diameter and height growth on trees treated with paclobutrazol (Profile 2SC) was less than on trees in all other treatments due to the growth-regulating effect of paclobutrazol. Root growth in the backfill soil was not affected by soil amendments added to the backfill soil at planting and was not affected by irrigation after planting in 5 of the 7 treatments.

  • Edward F. Gilman and Jason Grabosky

    https://hort.ifas.ufl.edu/woody/documents/articles/EFG0403.pdf

    Abstract. This study was designed to evaluate the impact of several planting depths and mulch depth, particle size, and placement on tree establishment. Except for one period 2 weeks after transplanting, mulch depth and mulch particle size did not affect first-year stress (stem xylem potential) or growth of 76 mm (3 in.) caliper, balled-and-burlapped, transplanted live oak (Quercus virginiana Mill.). Negative effects of deep [15 mm (6 in.)] mulch 2 weeks after transplanting occurred for the mixed particle–sized material only. Mulch placed over the root ball intercepted water, causing a drier root ball and resulting in greater tree stress and reduced survival following light applications of water than for trees with no mulch over the root ball. This result did not occur following heavy applications of water. Keeping the ground near trees free of vegetation chemically had the same effect on post-planting stress and growth as mulching did. Soil over the root ball resulting from deep planting intercepted water, resulting in more tree stress and greater likelihood of tree death in the first 4 weeks after planting. However, trees planted deeply were less stressed 3 months after planting. No root ball settlement occurred in the first 6 months after planting container-grown trees

  • Richard J. Hauer, Nilesh Timilsina, Jess Vogt, Burnell C. Fischer, Zach Wirtz, and Ward Peterson

    https://www3.uwsp.edu/cnr/Documents/MTCUS%20-%20Forestry/A%20Volunteer%20and%20Partnership%20Baseline%20for%20Municipal%20Forestry%20Activity%20in%20the%20United%20States%20-%20REDUCED.pdf

    Abstract. Communities cultivate citizen support of municipal forestry operations through volunteers and partnerships. Through a national census and survey of urban forestry activity in over 660 municipalities in the United States, researchers found two-thirds of all responding communities involve volunteers in tree activities. This increases from half of small communities (2,500 to 4,999 people) to all large communities (one million or more people) involving volunteers. When tabulated for the United States, a mean national estimate of 345,466 (195,754 SEM) people volunteered 1,484,204 (665,460 SEM) hours with municipal tree activities. This equates to 714 (320 SEM) full-time equivalent (2,080 hour-base year) positions. Overall, volunteers completed nearly 5% of municipal tree care activities. Nearly 80% of the municipalities train their volunteers. Tree planting (85% of communities) was the most common activity, followed by tree watering (40%), awareness/education programs (39%), tree pruning (28%), and fundraising (20%). Findings were contrasted with U.S. census population groups to disaggregate if volunteerism varied by community size. Volunteers were more commonly involved in communities with a greater urban-forestry capacity derived from a sustainability index score. Six attributes of municipal forestry program had either positive (+) or negative (-) effect on volunteer participation in urban forestry activities. These included adequate budget (-), per capita spending (-), tree board (+), outreach (+), strategic plan (+), and total employment (+)

  • E. Gregory McPherson

    https://joa.isa-arbor.com/request.asp?JournalID=1&ArticleID=3333&Type=2

    Abstract. Million Trees LA (MTLA) is one of several large-scale mayoral tree planting initiatives in the United States, striving to create more livable cities through urban forestry. This study combined field sampling of tree survival and growth with numerical modeling of future benefits to assess performance of MTLA plantings. From 2006 to 2010 MTLA planted a diverse mix of 91,786 trees. Survivorship rates of 79.8%, 90.7%, and 77.1% for street, park and yard trees were relatively high compared to other studies. Growth rates averaged 0.99 and 1.1 cm DBH per year for street and yard trees. They were similar to rates for the same species in Claremont, California, U.S., and trees in other subtropical urban forests. Projected over 40 years, the amounts of CO2 stored per tree planted per year (20.1 kg), avoided emissions (27.7 kg), rainfall interception (1.5 m3 ), and air conditioning savings (47.4 kWh) exceeded estimates from a previous assessment. One reason is that MTLA has planted more larger-stature trees than anticipated. Avoided CO2 emissions from energy savings were relatively large because trees were judiciously located for building shade. Park tree plantings were projected to store the most CO2 (42.0 kg per tree per year) because of their large-stature and high survival rate. Although MTLA has not reached its goal of planting 1 million trees, early results suggest that it is achieving success in terms of tree survival, growth, and performance. Continued success will depend on proper tree care practices, strategically selecting and locating new trees, monitoring threats, and adapting to challenges that arise.

  • Randall H. Miller and Robert W. Miller

    https://auf.isa-arbor.com/content/isa/17/7/185.full.pdf

    Abstract. Planting survival rates were determined for commonly planted street trees in Wisconsin. Removal records provide evidence of a four year establishment period. With a few exceptions, survival was found to be generally independent of species/cultivar selections in the cities of Milwaukee and Stevens Point, but significant differences were found in the city of Waukesha. Recommendations are made regarding species/cultivar use.

    Evidence of a four-year establishment period is consistent with conjecture by Miller (13) suggesting that a five year period be allowed before planting success can be realistically evaluated. Watson and others (18) found that a period of four or more years of stress followed transplanting of 5 to 10 cm diameter trees. They concluded that this is a function of the time needed to replace root loss due to transplanting. Other factors contributing to the loss of small trees in this period include vandalism and unintended injuries, such as mower damage

  • Sarah K. Mincey and Jessica M. Vogt

    https://joa.isa-arbor.com/request.asp?JournalID=1&ArticleID=3310&Type=2

    Abstract. A growing number of municipalities and nonprofits work with private citizens to co-produce the public benefits associated with urban forests by providing sizeable young trees to neighborhoods that agree to plant and water the trees for the critical first few years after planting. Little research has addressed the effectiveness of such programs or the extent to which variation in neighborhood maintenance and watering strategies may be related to biophysical and social outcomes. Without such knowledge, tree-planting investments are at risk of being a sink of public or charitable funds. This paper presents a case study of Keep Indianapolis Beautiful, Inc.’s neighborhood tree plantings in Indianapolis, Indiana, U.S., where researchers explored the relationship of neighborhood watering strategies with planted-tree outcomes, and with subsequent collective activities. The study authors observed neighborhood variation in whether trees were watered by individuals or collectively (groups of individuals), whether signed watering commitments were utilized, whether monitoring of watering occurred, and whether monitoring and subsequent sanctioning (when necessary) changed watering behavior. Results demonstrate that collective watering, signed watering agreements, and monitoring/sanctioning that changed behavior were positively associated with tree survival. Collective watering was also positively associated with subsequent collective activities, such as a neighborhood clean-up or block party. Such findings can improve the guidance offered by municipalities and nonprofits to neighborhoods for the management of successful tree-planting projects, and can ultimately improve the survival, growth, and thereby benefits provided by neighborhood-planted trees

  • Nowak, McBride & Beatty (1990)

    https://www.fs.usda.gov/research/treesearch/18718

    Abstract: Two-year growth and mortality rates were analyzed for 254 black locust, 199 southern magnolia and 27 London plane trees planted along a major boulevard extending from southern Berkeley through western inner-city Oakland, California. After the first two years, 34% of these newly planted trees were either dead or removed. The average annual mortality rate was 19% with no significant difference in mortality among the species or between years. Areas of lower socio-economic status exhibited the most tree mortality with percent mortality most strongly correlated with percent unemployment (r=0.78). Trees with adjacent land uses of apartments and public greenspaces had significantly high mortality while trees next to single family houses and rapid transit stations exhibited low mortality.

    The social environment around the tree is just as important as the physical tree environment for insuring early tree survival. A more intensive effort of public education and involvement should be sustained

    Description text goes here

  • Nowak, Kuroda, & Crane, 2004.

    https://www.fs.usda.gov/ne/newtown_square/publications/other_publishers/OCR/ne_2004nowak01.pdf

    Abstract. Based on re-measurements (1999 and 2001) of randomly-distributed permanent plots within the city boundaries of Baltimore, Maryland, trees are estimated to have an annual mortality rate of 6.6% with an overall annual net change in the number of live trees of -4.2%. Tree mortality rates were significantly different based on tree size, condition, species, and Land use. Morus alba, Ailanthus altissima, and trees in small diameter classes, poor condition, or in transportation or commercial - industrial land uses exhibited relatively high mortality rates. Trees in medium- to low-density residential areas exhibited low mortality rates. The high mortality rate for A. altissima is an artifact of this species distribution among land use types (24% were in the transportation land use). Based on a new tree population projection model that incorporates Baltimore's existing tree population and annual mortality estimates, along with estimates of annual tree growth, Baltimore's urban forest is projected to decline in both number of trees and canopy area over the next century. Factors affecting urban tree mortality are discussed.

  • Lara A. Roman & John J. Battles & Joe R. McBride

    https://nature.berkeley.edu/battleslab/wp-content/uploads/2015/03/Roman_2013.pdf

    Abstract Street trees have aesthetic, environmental, human health, and economic benefits in urban ecosystems. Street tree populations are constructed by cycles of planting, growth, death, removal and replacement. The goals of this study were to understand how tree mortality and planting rates affect net population growth, evaluate the shape of the mortality curve, and assess selected risk factors for survival. We monitored a street tree population in West Oakland, CA for 5 years after an initial inventory (2006). We adapted the classic demographic balancing equation to quantify annual inputs and outputs to the system, tracking pools of live and standing dead trees. There was a 17.2 % net increase in live tree counts during the study period (995 in 2006, 1166 in 2011), with population growth observed each year. Of the live trees in 2006, 822 survived to 2011, for an annual mortality rate of 3.7 %. However, population growth was constrained by high mortality of young/small trees. Annual mortality was highest for small trees, and lower for mid-size and large trees; this represents a Type III mortality curve. We used multivariate logistic regression to evaluate the relationship between 2011 survival outcomes and inventory data from 2006. In the final model, significant associations were found for size class, foliage condition, planting location, and a multiplicative interaction term for size and foliage condition. Street tree populations are complex cultivated systems whose dynamics can be understood by a combination of longitudinal data and demographic analysis. Urban forest monitoring is important to understand the impact of tree planting programs.

  • Emily Jack-Scott, Max Piana, Blake Troxel, Colleen Murphy-Dunning, and Mark S. Ashton

    https://joa.isa-arbor.com/article_detail.asp?JournalID=1&VolumeID=39&IssueID=4&ArticleID=3282

    Abstract: Over the last two decades, there has been a substantial increase in street tree plantings across the United States. Many cities have set ambitious planting goals, relying on volunteer community groups to meet them. Existing research demonstrates that community stewardship increases the survival of urban street trees. There is a lack of research, however, on how defining characteristics of community groups affect the survival and growth of the trees they plant. This study explores the significance of community group size (# participants), type (apartment, block watch, church, concerned neighbors, park, public housing, school, and social service), planting longevity (# years active), experience level (# trees planted), and neighborhood (geo-political boundaries). Measured for this study were 1393 trees planted from 1995 to 2007, by 134 groups, through the Urban Resources Initiative’s Community Greenspace program in New Haven, Connecticut, U.S. There was an overall survival rate of 76%. Highest survival and growth was found among trees planted by groups with more planting experience, greater longevity, and more participants. Higher tree survival and growth was observed when trees were planted by groups working in line with their mission (e.g., park groups in parks). Lowest survival and growth was found among yard trees planted by public housing groups. Existing canopy cover and neighborhood percent homeownership had little effect on survival or growth. This research can offer guidance for city managers by suggesting which planting groups require particular assistance in conducting successful, lasting street tree plantings.

  • Sklar & Ames. 1985

    https://www.tandfonline.com/doi/abs/10.1111/j.1467-9906.1985.tb00077.x

    A study was conducted from 1978 to late 1984 of the survival of inner-city street trees planted by the Oakland, California urban forestry program. The tree survival rate of approximately 60 to 70 percent from the trees planted in neighborhood parkways through urban forestry sponsored block parties contrasted sharply with less than one percent survival of trees planted earlier by the Model Cities program without community participation or ceremonial plantings. Explanations for the high tree survival were tested using participant observation, interviews with residents, and a small panel. Tree survival was not found to be related to the explanations provided by urban forestry ideology; namely, that residents had been educated to hold both instrumental and expressive values toward trees. Rather, the explanation appeared to be the function of an unintended solution to the issue of parkway ownership. The tree planting process which included species selection meetings and tree planting ceremonies tended to define the parkway trees as a resident's property, thus decreasing the significance of the parkway-property barrier.

  • Gary W. Watson and T. Davis Sydnor

    https://joa.isa-arbor.com/article_detail.asp?JournalID=1&VolumeID=13&IssueID=5&ArticleID=2153

    Abstract: Pruning root systems of landscape-size Colorado blue spruce [Picea pungens Engelm.) root systems in the nursery, 5 years before transplanting, increased the number of roots and the amount of root surface area in the root ball. The total root surface area of the harvest-ready 2m tall trees was increased from 122,000 cm2 to 245,000 cm2. The root ball of the root-pruned trees contained approximately four times as much root surface area as trees that were not rootpruned. Root balls of root-pruned trees contained 11.8 percent of the whole root system compared to 5.8 percent in root balls of unpruned root systems. Sixty percent of the pruned root systems were inside the dripline compared to 40 percent of the unpruned root systems. The increased absorbing root surface transplanted with the pruned trees should help to increase survival and reduce transplanting shock.

  • Daniel J. Wattenhofer, Gary R. Johnson

    https://www.mnstac.org/uploads/2/0/9/3/20933948/understanding_why_young_urban_trees_die_can_improve_future_success.pdf

    ABSTRACT The first several years after planting a tree, referred to as the establishment period, are recognized to have the highest annual mortality rates; determining those factors that influence survival of young trees should be considered paramount. This research examined several factors that influence young urban tree mortality: nursery production type (i.e. bare root, gravel bed bare root, container, or balled and burlapped), tree taxa, planting location type, and “planted by” (i.e. “who” planted the tree). The results from this study supported several relationships between project variables and young tree mortality, most notably that trees planted as containerized or balled-and-burlapped rootstock types in boulevards and parks had significantly higher survival rates than bare-root trees. Nursery production type, tree planting location, and tree taxa all had statistically significant impacts on young tree mortality, but “planted by” was not significant. The highest mortality rates were experienced by all trees planted in park/public spaces. The conclusions of this research will help to fill gaps and build upon the existing body of literature that practitioners may draw from to make informed planting and care decisions.

  • Christina Wells, Karen Townsend, Judy Caldwell, Donald Ham, E. Thomas Smiley, and Michael Sherwood

    http://ctufc.org/wp-content/uploads/2018/03/Effects-of-Planting-Dept-on-Tree-Survival.pdf

    Abstract. Landscape trees are frequently planted with their root collars below grade, a practice that may predispose them to transplant failure and girdling root formation. The objective of the present research was to examine the effect of planting depth on the health, survival, and root development of two popular landscape trees, red maple (Acer rubrum) and Yoshino cherry (Prunus × yedoensis). Trees were transplanted with their root flares at grade, 15 cm (6 in) below grade, or 31 cm (12 in) below grade. Deep planting reduced the survival of Yoshino cherries: 2 years after transplant, 50% of the 15 cm (6 in) and 31 cm (12 in) deep-planted cherries had died, whereas all the cherries planted at grade had survived. Survival of maples was not affected by planting depth. Deep planting also influenced the development of girdling roots. Three years after transplant, maples planted at grade had 14% of their trunk circumference encircled by girdling or potentially girdling roots; this number rose to 48% and 71% for 15 cm (6 in) and 31 cm (12 in) deep-planted maples, respectively. There were no treatment-related differences in girdling root development in the cherries. These results are consistent with arborists’ observations that deep planting is a significant source of stress in landscape trees.

  • ISarah Widney, Burnell C. Fischer and Jess Vogt,

    https://www.mdpi.com/1999-4907/7/3/65

    Abstract :Trees provide numerous benefits for urban residents, including reduced energy usage, improved air quality, stormwater management, carbon sequestration, and increased property values. Quantifying these benefits can help justify the costs of planting trees. In this paper, we use i-Tree Streets to quantify the benefits of street trees planted by nonprofits in three U.S. cities (Detroit, Michigan; Indianapolis, Indiana, and Philadelphia, Pennsylvania) from 2009 to 2011. We also use both measured and modeled survival and growth rates to “grow” the tree populations 5 and 10 years into the future to project the future benefits of the trees under different survival and growth scenarios. The 4059 re-inventoried trees (2864 of which are living) currently provide almost $40,000 (USD) in estimated annual benefits ($9–$20/tree depending on the city), the majority (75%) of which are increased property values. The trees can be expected to provide increasing annual benefits during the 10 years after planting if the annual survival rate is higher than the 93% annual survival measured during the establishment period. However, our projections show that with continued 93% or lower annual survival, the increase in annual benefits from tree growth will not be able to make up for the loss of benefits as trees die. This means that estimated total annual benefits from a cohort of planted trees will decrease between the 5-year projection and the 10-year projection. The results of this study indicate that without early intervention to ensure survival of planted street trees, tree mortality may be significantly undercutting the ability of tree-planting programs to provide benefits to neighborhood residents.

    The main management implication of this study is that ensuring the survival of planted street trees is most important for providing future benefits; each dead tree represents a loss of $40–$50 in annual benefits for the city each year after the tree dies.