Crataegus phaenopyrum or Washington hawthorn, is non-native to Ontario with a range that encompasses the eastern half of the United States, from southeastern Pennsylvania and New Jersey to Florida, and westward to southeastern Missouri. It thrives in well-drained soils, adapts to various pH levels, and tolerates urban pollution. While it supports pollinators with its spring blooms, its thorns make it unsuitable for recreational areas. This hawthorn drops small red fruits in fall and sheds leaves in autumn, creating moderate levels of litter. Transplanting is easiest in spring.

Crataegus viridis, or winter king hawthorn, is non-native to Ontario, originating from southeastern U.S. from Virginia to Florida west to Texas and up the Mississippi River valley to Illinois. It grows well in average, dry, and medium well-drained soils in full sun. It is known for its high disease resistance compared to other hawthorn species. It produces edible berries but may be best to leave for other wildlife rather than human consumption. This species is mostly spineless,containing only occasional thorns and is tolerant of pollution, making it suitable for urban environments. However, its flowers have an unpleasant scent.

Diospyros virginiana, or common persimmon, is non-native to Ontario, originating from southern Connecticut and Long Island, south to Florida, and west to Texas, Louisiana, Oklahoma, Kansas, and Iowa, and are appreciated for its fruit and appeal to wildlife. Both male and female trees are needed for fruit production, and it is adaptable to various soil pH and moisture conditions. The tree typically faces few diseases, or insect issues and has a deep root system that supports successful establishment. Leaf spot may occur, but overall, the tree does not suffer from serious pest or disease problems. Diospyros virginiana can be messy due to its sweet, edible fruits that drop in the fall, potentially attracting wildlife and creating litter.

NOT RECOMMENDED TO PLANT: INVASIVE TENDENCIES. Elaeagnus angustifolia, or Russian olive, is not recommended for planting, due to invasive tendencies. This species is non-native to Ontario with a natural range in Asia and limited areas of eastern Europe. It can thrive under a wide range of soil textures including sand and heavy clay, and can withstand flooding and silting, however, it grows best in deep sandy or loamy soils with only slight salt and alkali content. The tree has an aggressive root system and fast growth rate, and it spreads via birds which allows it to outcompete native species. The Auditor General of Ontario has specifically flagged this tree species as a concern in the nursery trades ("Value-for-Money Audit Management of Invasive Species," 2022), and as such should not be recommended for planting. For an alternative native to North America, consider Amelanchier spp.

Eucommia ulmoides, or hardy rubber tree, is a versatile, low-maintenance shade tree with a broad, spreading canopy and glossy green leaves. Native to China, it thrives in full sun and adapts to various pH levels and drought conditions. While its flowers are inconspicuous, the tree's rounded form makes it a great landscaping choice. As the name suggests, rubber can be created from its sap, though it is too expensive for commercial use. It is generally pest and disease free, though its branches may be susceptible to storm damage. For a durable and attractive shade tree, the hardy rubber tree is a reliable option. Currently limited availability in the nursery, but could become more commercially available with demand.

Euonymus atropurpureus, or burning-bush euonymus, is primarily found in the Midwestern United States, but its range extends from southern Ontario south to northern Florida and Texas. It prefers average to medium well-drained slightly acidic soil in full sun to partial shade. Burning bush is known for its vibrant red fall fruit and colourful foliage, but its poisonous fruit makes it unsuitable for areas frequented by people. Consider alternatives like Rhus aromatica or Rhus typhina. While adaptable to various soils, it requires protection from deer and rabbits.

NOT RECOMMENDED TO PLANT: INVASIVE TENDENCIES. Euonymus europaeus, or spindle tree, is not recommended to plant, due to its invasive tendencies. It is native to Europe and western Asia. It prefers well-drained sandy soil. All parts of the plant, including berries and flowers are toxic and should not be consumed. It has weedy tendencies, particularly in the Midwest United States, and can spread uncontrollably in garden settings. Consider planting Euonymus atropurpureus as an alternative.

Fagus grandifolia, or American beech, is an native tree to Ontario, with a range spanning the east coast of US and Canada that provides vital wildlife habitat and food source. It prefers moist, well-drained, acidic soil and doesn't tolerate wet or compacted soil. Known for its long lifespan, 200 to 300 years, it produces edible triangular nuts in spiny bracts, ripening in the fall. While American beech is a great addition to woodlands and naturalized areas, it requires careful consideration due to its shallow root system, which makes it susceptible to drought, wet sites, and salt. This species can consume vast quantities of water and with its surface roots may reduce water availability for surrounding plants and garden areas. Beech trees can be moderately messy in autumn due to falling seed husks and leaves, but their ecological benefits make them a wonderful addition to your landscape.

Fagus sylvatica, or European beech, is a non-native tree that thrives in alkaline pH soils compared to its native counterpart the American beech. It is native to large parts of Europe. Although tolerant to alkaline pH soil, it struggles in wet, compacted soils and urban environments with heavy foot traffic. It's best suited for large spaces like parks or open fields, and are generally considered resistant to deer and rabbits. Beech nuts are toxic if consumed raw or unripe, but otherwise are edible. This tree requires continual watering during dry periods and benefits from mulch to retain moisture. This species is very common in the nursery and has high availability.

Fraxinus americana, or white ash, is not recommended to plant, due to its high vulnerability to the emerald ash borer, a pest that has decimated ash populations in Ontario. While native to Ontario, white ash requires regular insecticide treatments to manage infestations, making it a poor or costly choice in areas affected by the borer. To that end, white ash appears to be more resistant to borer than other ash species except for blue ash. It prefers moist, organically rich, well-drained loamy soils in full sun.

CAUTION: MAY HAVE INVASIVE TENDENCIES. Fraxinus excelsior, or European ash, is not recommended for planting due to its susceptibility to the emerald ash borer, which has devastated ash populations. Although, it may be less susceptible to EAB than North American ash species. This species is native to western Asia. While it prefers moist, well-drained soil and full sun, European ash is vulnerable to storm damage due to brittle branches and can be somewhat messy, shedding large quantities of seeds and leaves in the fall.

Fraxinus nigra, or black ash, is not recommended for planting due to its high susceptibility to the emerald ash borer, which has devastated ash populations. Black ash is native to eastern North America, specifically from western Newfoundland to southeastern Manitoba and south to Iowa, Illinois, and northern Virginia. It prefers moist, swampy conditions that have poor drainage.

Fraxinus pennsylvanica, or green ash, is not recommended for planting due to its high susceptibility to the emerald ash borer, which has decimated ash populations. This species was once a dominant canopy tree across most municipalities in Ontario. It prefers moist, fertile soils ranging from sandy, to clay loam, with a preference for well-drained conditions. This species, along with the elm, have taught many urban foresters to diversify their canopy.

Fraxinus profunda, or pumpkin ash, is not recommended for planting due to its high susceptibility to the emerald ash borer, which has devastated ash populations. Native to eastern North America, this large tree thrives in moist, wet soil and requires full sun to light shade. Its trunk develops a swollen, buttressed base, giving it a "pumpkin" shape, which is how it gets its name.

Fraxinus quadrangulata, or blue ash, is recommended for planting compared to other ash species, but with caution. Research has indicated this species is less susceptible to emerald ash borer than other ash species. Native to central North America, specifically from southwestern Ontario and Michigan to southern Wisconsin, south to West Virginia, Georgia, Alabama, and west to Kansas and Oklahoma. Blue ash thrives in dry to medium wet, well-drained soils and is one of the most tolerant ash species for dry sites. It gets its name from the blue dye that can be extracted from its inner bark. Historically valued as a shade, street, and lawn tree, its adaptability is overshadowed by green ash.

Ginkgo biloba, or ginkgo, is a non-native to Ontario, originating from China. It is a hardy, low-maintenance tree known for its unique fan-shaped leaves that turn brilliant yellow in the fall. One of the oldest tree species, it is highly resilient, tolerant of salt, heat, drought, alkaline and acidic soil types, making it ideal for urban areas. Often called a "bulletproof" tree, ginkgo is pest-resistant and thrives in poor conditions. To avoid odour, plant male trees, as females produce messy, pungent seeds. Ginkgo grows best in full sun and well-drained, medium-moisture soils. While it grows slowly at first, it eventually develops a strong, spreading canopy.

Gleditsia triacanthos, or honey locust, is a cultivar of a tree native to Ontario. It is a durable, adaptable tree known for its tolerance to various soil conditions, drought, and road salt, as well as its small, yellow leaflets. It grows quickly in moist to well-drained soils, making it popular in urban and suburban landscapes. Overuse has led to potential biodiversity concerns so consider alternative tree options before planting honey locust, especially in park and residential areas.

Gymnocladus dioicus, or Kentucky coffeetree, is a resilient, low-maintenance tree native to Ontario, ideal for urban conditions. The native range of the Kentucky coffeetree extends from the southern Great Lakes region in the United States, east to New York, and south to Oklahoma, Arkansas, and Tennessee, with a very small, restricted Canadian population in southwestern Ontario. It thrives in moist, well-drained soils and full sun, tolerating drought, pollution, and alkaline pH. The tree gets its name from the seeds, which were once ground and roasted by Native Americans and early settlers to make a coffee-like beverage (though raw seeds are toxic). Known for its striking winter silhouette, the tree is largely pest free and perfect for large lawns and parks. Male trees are preferred for their lack of seed pods, while female trees, though visually striking, can be messy due to bulky seed pods and leaf drop.

Halesia tetraptera, or Carolina silverbell is non-native to Ontario with a natural range within the eastern United States. It is known for its stunning bell-shaped flowers in spring. It thrives in well-drained, acidic, and organically rich soils with full sun to part shade, and can suffer from chlorosis in high pH soils. While it may shed small leaves and seed capsules in the fall, creating occasional messiness, its adaptability and striking structure make it an excellent choice for shrub borders or as a standout specimen.

Hamamelis virginiana, or witch-hazel is native to Ontario with a natural range from Nova Scotia and Quebec in Canada to Florida and eastern Texas in the United States. It prefers moist, acidic, organically rich soils, and tolerates heavy clay soils. It is a resilient shrub known for its unique floral display and lovely fragrance and thrives in moist, well-drained soils with high organic matter and is perfect for naturalization, parks, and highways. Although slow growing, this species is tolerant of shade, pollution, clay soils, and even road salt. It's ideal for a variety of conditions, though it should be kept away from dry spots. Witch-hazel is deer-resistant, free from serious pest or disease issues, but does require sucker removal.

Heptacodium miconioides, or seven-son-flower, is native to China and is a unique ornamental shrub/small tree that is known for its fountain shape and fragrant white flowers. It prefers sandy loam soils supplemented with fertilizer. It is a great source of nectar for butterflies and hummingbirds and attracts a wide variety of pollinators. It is best to prune this species when young to establish its form, and may widen over time. It thrives in sun, or light shade, is easy to grow, and isn't fussy about soil type, however it does require regular watering during the establishment phase.

Ilex opaca, or American holly is a non-native to Ontario, and is a slow-growing evergreen tree that offers fragrant berries on female plants. Native to eastern and south-central United States, ranging from coastal Massachusetts south to central Florida, and west to southeastern Missouri and eastern Texas. Deer-resistant and tolerant of road salt, it thrives in acidic soils with part shade but can suffer in alkaline soils. While it's best suited for larger landscapes due to its size, it provides valuable nectar for pollinators, and is an attractive addition to your landscape. Both male and female trees are needed for fruit production.

Juglans cinerea, or butternut, native to eastern and midwestern North America, Ontario, is currently endangered due to the invasive butternut canker disease, which has devastated its population. It prefers deep, moist, well-drained soil, preferably with alkaline conditions to accommodate for their long tap root. While restoration efforts are underway, planting should be approached with caution, as the disease is widespread. Black walnut closely resembles butternut and provides a safer planting alternative, as butternut is also prone to blight, fire, storm damage, and grackle damage. Butternuts tolerate drought and browsing by rabbits but produce juglone, toxic to other plants. It sheds abundant leaves and hard-shelled nuts, leaving significant debris and residues on nearby surfaces, making it extremely messy. Despite these challenges, the tree has historical value, with its fruit once used for dye and its sap boiled for syrup.

Juglans nigra, or black walnut, also known as American walnut, is native to eastern North America, specifically from southern Ontario, Canada, south to Texas and Florida, and west to Minnesota and South Dakota. While it produces juglone, a chemical toxic to some plants, most tree species do not have an issue being planted with it. Black walnuts thrive in full sun with well-drained, organically rich soils, and are tolerant of both acidic and alkaline soils, as well as salt spray. Its yellow-green fruit feeds wildlife and supports the banded hairstreak butterfly. Though it is messy due to its fallen leaves and hard-shelled nuts, pruning is best done in the dormant season. While slow to produce nuts, black walnuts can yield significant crops after 20 years.

Juniperus virginiana, or eastern red cedar, is native to Ontario with a natural range extending from Nova Scotia and southern Ontario in Canada, south to northern Florida and eastern Texas in the United States. This species thrives in diverse soil conditions, from swamps to dry, rocky glades, though it prefers moist, well-drained soils and full sun. Eastern red cedar is quite resilient and is the most drought-resistant conifer in eastern North America, making it ideal for areas with fluctuating moisture. Highly salt-tolerant, it excels in urban landscapes, including roadsides and residential areas. Male plants produce small pollen cones, and female plants develop berry-like cones that ripen to blue gray, offering seasonal interest and food for wildlife.