1. Norway Maple Invasion Across the world invasive species are affecting plant and animal habitats. Plants that spread after they are brought into an area can become problems, changing the landscape and disturbing or reducing the amount of native populations. One kind of invasive species is the Norway Maple, also known as Acer platanoides. It has been causing problems for many native species, including the Sugar Maple. According to the University of Michigan, if nothing is done regarding the invasion of the Norway Maple in years to come there will be strong homogenizing of the Maples in forests across the United States. As a result this would lead to more plant extinctions, such as Sugar Maples, and the decrease in maple syrup production. Norway maples change the forest environment by altering the amount of light that enters the canopy, the composition of the soil, and the distribution and number of seedlings. The Norway Maple’s canopy can reach up to 70 feet when the tree is in adulthood. The Norway Maple’s canopy is also very dense, causing the ground below to not receive much sunlight. The problem with this is that the tree will give everything below a lot of shade. The lack of sunlight may cause difficulty for Sugar Maple seedlings, and it sets a clear path for the Norway Maple seedlings to grow because they can tolerate shady conditions. In a study done by Wyckoff in 1996 it showed that 83% of seedlings found under canopies were from Norway Maples. Also, according to the Reinhart study in 2005, where there are more Norway Maple canopies there is less native species diversity and open sky. In areas without Norway Maple canopies there were more diversities of plant life. Research done by Munger in 2003 shows that the Norway Maple grows very well in cool, moist, shaded environments, whereas other species (the Sugar Maple) may not grow well. With the lack of sunlight from the Norway Maple’s canopies, it also creates a lack of richness in the soil. Studies have also shown that the Norway Maple’s foliage produces an anti-fungal chemical that changes the composition of soil. The chemical alters the decomposer fungi that favors the growth of the Norway Maple as well as disturbing other species. All the factors (canopy and soil) come together and make it easier for the seedlings of the Norway Maple to grow and thrive. Studies by Wangen in 2006 show that the seeds establish within the seed shadows of parent trees. Also, research done by Michigan University showed that 99% of the Norway Maple seeds typically fall within approximately 50 meters of the parent tree. Road Salts Weather and climate have negatively affected maple syrup production in the past years. As said in an article I read, the 2005 and 2007 maple syrup productions were really low. The basal area is the diameter of the tree’s base. The best conditions for sugaring are just below freezing, which are in the upper 40s. The total production of maple syrup in New England was 1,237,000 and 61% was Vermont (New England Agricultural Statistics). The graph below shows the New England maple syrup production last year and the United States maple syrup production. "It pretty much stopped running," he says, though it was a relatively good season overall. "This year we made 122 gallons (All tapped out." The United Nations Intergovernmental Panel on Climate Change predicted that the temperature is going to rise 3-10 degrees in the next century and that is what is going to doom the maple syrup production industry. Climate kills sugar maples by not giving the trees enough sunlight to live. If sugar maples do not have enough warmth to keep themselves going. It can’t be too hot or too cold. Since the temperatures are expected to increase, the sugar maples are not expected to live. Weather and Climate Because of the burning of fossil fuels, driving cars, and running factories an increase of acid rain has affected the soil and decreased the amount of Sugar Maple trees in the northeast United States. Acid rain has caused more acidic soil, fewer seedlings sprout and mature, and more adult trees to die. The long term effect of human activity has caused an increase of acid rain and a decrease in sugar maples. The first symptoms usually are premature yellowing and reddening of leaves. Sugar maples ideally grow in calcium rich soils which is being decreased from acid rain. Also new seedlings cannot sprout due to a buildup of fallen maple leaves on the ground. Extra nitrogen from the acid rain increased leaf litter by up to 50%. Among all the trees, the ones in higher elevations, like the Appalachian mountains, are being affected the most. Sugar Maples dominate the hardwoods of northeast range, as far south as Virginia and as far west as Minnesota. One strange element about the sugar maple is that they will produce more and sweeter sap under stress. Acid Rain Norway MapleSugar Maple Many studies have correlated the negative effects with road salt on street side trees, especially effecting the Sugar Maple. Many environmentalists predict that in the future, these salts will kill the roadside maples that are already experiencing the effects of the salt. The beginning signs of the road salts impact on trees and plants, are browning of the leaves, wilting of the leaves, leaf loss, and eventually entire limb loss. After this comes total death to the tree, at the point where it can no longer support any of its own, self- sustained life, having its photosynthesis cycle come to an end. How Does Road Salt Kill Trees? The calcium chloride in road salt is naturally found in soil, however, in much smaller quantities. The calcium chloride is an active agent in trees development stages, regulating the nutrient uptake, and availability of nutrients in the trees general area of uptake. This natural event occurs in all trees, however, when human impact interferes with the normal amounts of CaCl 2, and large amounts of calcium chloride become in exposure to the trees, it becomes quite harmful. In large amounts of calcium chloride, the trees begin to die this is because the excess calcium chloride from the roads, that takes the place of other essential nutrients for the growth of trees, and therefore limits its ability to grow, and eventually causes the tree to die due to malnourishment. Or, another way that many trees die is when the road salt sprays from roadways onto the physical trees, this causes the effects of browning of the leaves, which we are currently seeing in many roadside maple’s and in some cases, limb loss, which will escalate into entire trunk death. Also there is no accurate measurement of the decline of the trees but, in the past 25 years the average height has decreased by 25 percent, and the general bulk of the trees has nearly declined by 50 percent. With the help of their parent tree, the seedlings are able to grow without any difficulty. The tree provides shade, perfect living conditions for the seedlings, and without sunlight other plants can’t live so the competition for nutrients is eliminated. According to a study done by Munger in 2003 Norway Maple saplings displayed an average annual height growth increment that was nearly twice that of nearby Sugar Maple and significantly higher rates of instantaneous water use efficiency than Sugar Maple saplings at the same site. These facts show that the Norway Maple has a higher tolerance of extreme conditions than the Sugar Maple, then causing the Sugar Maple to be pushed from certain parts of the forest. By: Corinne Gaccione, Thomas Lattarulo, Semyon Fedotov, and Alec Miller