		COMMUNITY SERVICES AND ENVIRONMENT COMMITTEE


	TO:	Mayor and Members of Council

	FROM:	Paul Ingham, General Manager, Operations

	PREPARED BY:	Mark Ingwersen, Manager, Parks Maintenance

	DATE OF MEETING:	September 13^th, 2004

	SUBJECT:	Norway Maple Report

RECOMMENDATION:

THAT the staff report entitled “Norway Maple Report”, dated September 13^th, 2004, be received;

AND THAT staff continue to prune, remove, replace, and/or fertilize Norway Maple boulevard trees as required within the approved 2004 Capital Budget;

AND THAT staff report back to Council in the fall of 2004 to provide specific numbers of Norway Maples pruned, removed, replaced, and/or fertilized in 2004, as well as anticipated funding necessary to support of a similar program in 2005, if required.

PURPOSE:

This report has been prepared to provide background information on the Acer Platenoides (Norway Maple) tree decline in the Town of Markham, and to update Committee and Council on the status of the replacement program.

BACKGROUND:

According to 1999 inventory numbers, there are approximately 18,000 Norway Maples on boulevards in the Town of Markham. In recent years it has been noted that our population of Norway Maples are under stress and their health is declining. All trees, including maple trees, experience many stresses when grown in urban areas. The collective result of the stresses is a decline in tree health and vigour, sometimes to the point of death. The decline of Norway Maples is not a disease per se, and is not contagious. Decline disease seems to be the result of complex interactions of abiotic and biotic factors that predispose or weaken the trees, followed by inciting or triggering events that result in dieback and mortality. The problem is not a new one, described as early as 1917 in Massachusetts. Many of these problems are not specific to just maple trees, as oaks, ash, sugar maples, pin oaks and other street trees are also susceptible.

Factors contributing to tree decline include; leaf scorch, lack of water, girdling roots, salt injury, soil compaction, frost, wind damage, and grade changes. These produce conditions that may allow secondary problems such as verticillium wilt, anthracnose and other fungal disease to manifest themselves. However, tissue analyses from the University of Guelph, of dead Norway Maple trees in Markham has indicated that secondary agents or diseases are not present.

Based on the best information available at this time staff believe that climatic factors triggered the decline/death of Norway Maples in the Town of Markham. These factors include successive wet springs and falls and summer droughts, with the culminating factor being extremely warm temperatures in March 2003 followed by severe cold in early April, then 3 days above 20°C in mid April, and 3 nights of below freezing temperatures at the end of April. These extreme swings, combined with previous stress factors have resulted in the decline/death of Norway Maples in Markham.

Symptoms indicating decline include:

Undersized foliage and pale colour
Leaf scorch or chlorosis.
Late spring flush of leaves
Decrease in twig and stem growth
Premature fall colouration and leaf drop
Water sprouts may grow from the branches and trunk
Thinning in the upper crown foliage becomes evident as twigs die back
Larger branches die as the decline progresses
Heavy seed formation may occur

To reduce the stress and limit the increase of the decline on trees, the following practices have been put into place to increase the trees’ chances for survival.

Affected trees will be watered thoroughly during drought periods
A fertilizer application will be performed on those trees that are exhibiting signs of decline but still appear viable.
The dead wood will be pruned out to allow trees to recover and prevent a vector for disease and insects.
Any trees that are dead or have declined to the point of becoming a hazard have/will be removed and replaced.

In the spring of 2003, based on calls from residents, the Forestry Section inspected 348 Norway Maple trees. Removal of 93 trees was necessary, and the replacement trees were planted in the spring of 2004.

The large volume of calls from concerned residents prompted a letter to be sent out to each concerned resident, informing them of the Norway Maple decline, and the actions the Town was undertaking. Council received similar information via an e-mail sent June 26, 2003, and residents and Council were updated again on October 3^rd, 2003.

Forestry staff responded to every call from residents by inspecting their tree and determining whether the tree posed an immediate public safety hazard. If there were no immediate safety concerns, the tree was monitored on an ongoing basis to determine whether the tree would decline further. Forestry staff established an inventory of these trees, based on the calls received, and monitored the trees over the summer and fall of 2003, which allowed staff to determine the number of trees requiring pruning, or removal and replacement in 2004.

OPTIONS/DISCUSSION:

Of the 348 trees inspected in 2003, 93 were dead and required removal. Of the remaining 255 cases identified in 2003, all were re-inspected by staff in 2004. During the inspection of these cases staff discovered an additional 359 trees in similar decline immediately adjacent to the previously inspected trees, which had not yet been identified, resulting in a total of 614 trees inspected/re-inspected to date in 2004. It was found that out of this inventory of 614 trees, an additional 61 require removal, replacement and stumping, while the remaining trees require pruning and fertilizing.

After all the trees were assessed in June 2004, and prior to any work being conducted, an additional letter was given to residents outlining the course of action that is required for their boulevard tree(s). At that time staff also provided residents with door hangers asking residents to water the Norway Maple trees if necessary under drought conditions.

As stated above, the Norway Maple decline was as a result of climatic conditions. This situation was an anomaly, and a similar occurrence at a slightly different time of year may have spared Norway Maples but may have been detrimental to other species. Consequently, the Town can continue to plant Norway Maples among other species of replacement trees. Forestry staff will continue to plant a large variety of trees to avoid a monoculture, which would leave the tree population prone to severe decline should environmental factors severely effect any one species.

Staff will update Council in fall 2004 identifying the final number of trees affected, and pruned/replaced in 2004. In addition, staff will identify additional resources required, if any, to complete any newly identified work for 2005.

FINANCIAL CONSIDERATIONS:

The cost to remove and stump the 93 trees removed in the fall of 2003 was absorbed in the 2003 Operating budget. The cost to plant the 93 replacement trees in spring 2004 is $25,000.

The remaining 255 cases identified in 2003 and the 359 new cases in 2004 total 614 trees. Of the 614 cases 61 trees will be removed and replaced at a cost of $17,000. The remaining 553 viable trees will require pruning, and staff will conduct 50% of this work in house, while the remainder will be contracted out at a cost of approximately $47,000. The in-house pruning will pre-empt the Forestry Section block pruning program for 2004. To fertilize the remaining viable trees will cost approximately $11,000.

Funding for the work to be conducted is provided for in the Capital Budget Account # 059-6150-6194-005, Norway Maple Tree Maintenance in the amount of $100,000. In summary, staff anticipates the following expenditures:

· The cost to replace the 93 trees removed in the fall of 2003 was $25,000.

· The cost to remove and replace the estimated 61 trees that have died since fall 2003 will be $17,000.

· The cost to contract out pruning of 553 viable trees will be $47,000.

· The remaining $11,000 will be used to fertilize viable trees as required.

Total Cost: $100,000


Paul Ingham, General Manager, Operations		Peter Loukes, P. Eng. Director, Operations and Asset Management

Jim Sales, Commissioner of Community & Fire Services

Q:\Commission Share\Operations and Asset Management\Reports\2004\Operations\Norway Maple Report\Norway Maple Report.doc