Types of maple trees in ontario full#

It is also important to note some newer cultivars that have been developed for street tree use in eastern North America. By planting them away from naturalized areas and using them in plantings that are diverse in species, some cultivars of Norway maple can help build our urban % forest cover while posing very little invasive threat. Norway maple cultivars with lower germination, seed number and flower production may be worth investing in if the site is a stressful urban one. “Crimson King’ and ‘Globosum’ also have a significantly smaller canopy than the species. Not only do ‘Crimson King’ and ‘Faasen’s Black’ produce lower numbers of seeds, the seed also has the lowest rates of germination. ‘Crimson King’, ‘Faasen’s Black’ and ‘Globosum’ all produce the fewest amounts of flowers and therefore the least number of viable seeds. Of the many different cultivars of Acer platanoides, research indicates that there are some that are less invasive. When we do the math we see that ‘Crimson King’ has less than 1% viable seed compared to the original Norway maple species. That means that ‘Crimson King’ has less than 1% viable seed than the original species does.įlowers of Acer platanoides ‘Crimson King’. ‘Crimson King’) that will produce < 10% the amount of seed that the original species does – and that seed is quite low in viability (10%). Norway maple, the original species, produces copious amounts of seed and a large proportion (75%) of that seed is able to germinate and produce another tree if it finds suitable conditions. They found that some cultivars of Norway maple pose a much smaller risk to our natural areas. Research conducted at Penn State University evaluated several cultivars of Norway maple and the original species. By knowing which cultivars which provide the lowest viable seed, we can make more informed choices and reduce the impact to natural ecosystems. These selected cultivars of Norway maple differ in flower number, seed quantity, germination time, and seed viability from the original species. They want red-leaved cultivars of Norway maple (e.g. The truth is, many urban landscapes are so disturbed, they won’t support populations of native plants anymore.Īnd what do homeowners want to buy when it comes to planting trees in their yards? It probably won’t surprise you to know that one of the most popular trees purchased are those “red-leaved maples”.

Types of maple trees in ontario full#

We used to be able to plant some native maples in urban landscapes decades ago…until residential properties became so small and were graded with such poor soils that many native species will not survive, or will never reach their full potential and often become a hazard. Many horticulturalists are concerned that there is insufficient scientific criteria used to classify these as “invasive species” and hope that there will be exceptions where appropriate. Some of these are key urban landscape and green roof plants. Part of the strategy includes efforts to stop the production and sale of several commonly used ornamentals in Ontario. Most recently, the Invasive Species Act was developed to help reduce the spread of invasive species. There are some groups that feel it should be illegal to grow and plant Norway maples here in Ontario. Norway maple (Acer platanoides), the original species, developing seed.Īs you know, the Norway maple species has become labeled as an invasive species in some parts of North America. The problem is that the uncultivated (original) species produces large amounts of seed and those seedlings are very shade tolerant and therefore may spread into naturalized areas.įor decades now, North American nurseries have been offering a wide range of cultivars of Acer platanoides, and these cultivars differ significantly from the original species.

It was recommended by the ministry of natural resources and grown in their nurseries.

Norway maples tolerate pollution, hot, dry conditions and a wide range of soil pH’s which make them a very important and successful street tree, sometimes where little else would grow. The Norway maple ( Acer platanoides) has been a successful street tree, lining several streets and providing shade and habitat in several cities in Canada and the US. We weren’t thinking about how easy we were making it for pests to spread and infest trees along these long, continuous rows. Of course it was a mistake to plant so many of one species (or one cultivar). The ash tree was a popular and drought resistant species…until emerald ash borer came along. Our streets used to be lined with gorgeous, vase-shaped elms…until Dutch elm disease came along. Acer platanoides ‘Crimson King’ (When you consider all of the trees that are grown for street plantings in the urban landscape, you will quickly come to realize that the number of possibilities can be quite small because of poor soil conditions and exposure.