Acer Campestre or the Field Maple is a type of flowering plant classified as Kingdom Plantae, Family Sapindaceae, Genus Acer. These trees are native to the regions of Britain, Southwest Asia from Turkey to Caucasus, North Africa in the Atlas Mountain, and continental Europe including Denmark, Poland, and Belarus. These trees are also found widely in regions outside of Europe, such as the United States of America, and Western Australia. This tree species is often widely grown as an ornamental tree in parks and other locations.
Acer campestre (Field Maple) trees are deciduous in nature, which means they shed their leaves depending on the seasons. They have barks which are corky in texture, with brown colored shoots. The leaves of this tree are paired together in a combination of long and broad leaves, with rounded smooth edges. The flowers of the Acer campestre (Field Maple) are produced in spring season while the leaves are yellow-green in color.
Acer campestre (Field Maple) bonsai trees are quite popular among bonsai enthusiasts, specifically due to the dwarf cultivar Microphyllum. These bonsai trees have a distinct appearance compared to other bonsai maples, and have very translucent and frilly leaves. They can grow up to 8 meters in height, with stout trunks and rough barks. This species responds well to management such as ramification and leaf reduction, so taking care of this bonsai tree is fairly easy. They also have a rapid rate of growth, similar to other maple bonsai tree species. This species of Bonsai is not commonly found in nurseries, however, as opposed to other bonsai maples like the Japanese and Trident maple bonsai trees.
This field guide is an attempt to help bonsai enthusiasts learn more about growing and maintaining Acer campestre (Field Maple) bonsai trees.
How long does it take to grow Acer campestre (Field Maple) Bonsai?
The Acer campestre (Field Maple) Bonsai is a very fast-growing Bonsai that is flexible to work with. They need to be constantly maintained and repotted every two years to ensure healthy growth. They also grow faster in open soil, as it allows quick thickening. If these bonsai trees are left unpruned, the gaps between the buds on the shoots can get too long, which will hamper their tightness of growth.
Position and lighting
Acer campestre (Field Maple) Bonsai trees require partial or full sunlight through their growing season. While young, these trees can experience leaf scorch during the summer seasons and need protection from the sun. But these trees are very hardy during the winters and can withstand very low temperatures. Most bonsai owners do not relocate Acer campestre (Field Maple) Bonsai trees during the winter. One thing to keep in mind is to offer protection to these trees in the winter if the trees are young, or being grown in very small pots.
Temperature requirements
This species of maple bonsai trees is very hardy by nature and easy to maintain. They are particularly hardy during the winter seasons when bonsai owners do not need to move the plants even in cold temperatures. But smaller bonsai trees need to be frost protected during the winter.
You can also keep Acer campestre (Field Maple) Bonsai trees in full sunlight as long as they have sufficient water.
Soil
Acer campestre (Field Maple) Bonsai trees grow well in Akadama bonsai soil, due to its helpful quality of retaining water and nutrients. Including a grit of organic mix along with the soil would be ideal. Clay, sand, acidic, alkaline, well drained, loam types of soil all work well with this bonsai species.
Watering needs
These Bonsai Trees are flexible, and can tolerate hard tap water, although they prefer natural rain water. Try to avoid over watering or leaving the tree too dry. Acer campestre (Field Maple) Bonsai trees require cool roots or else they start to wilt. But reduce watering during the winter seasons.
Feeding
Standard bonsai food, half strength plant food, or time release pellets every two weeks once, especially during the growing season, is sufficient for this bonsai. If you want a thicker tree with faster growth, you can feed it heavier than usual. Limit feeding to reduce coarseness of the new growth.
Styles
Acer campestre (Field Maple) Bonsai Trees are an upright growth species of Bonsai. They offer great flexibility in styles, such as in groups or individually; potted or open soil. They adapt well to most styles such as formal upright style, forest style, informal broom style, etc, except Literati style. It is preferable if grown in the range of medium to large sizes but they can adapt to smaller growth sizes as well.
How to Plant and Grow Acer campestre (Field Maple) Bonsai?
Acer campestre (Field Maple) Bonsai Trees are best grown in open soil due to their fast rate of growth. These maple bonsais are very tolerant of root pruning. They have a dense, fibrous root system that adapts well to bonsai cultivation. Ensure to feed the tree well during growth season and water regularly, while keeping the soil moist. Because these trees are suitable for bonsai growth, they grow rapidly on their own with regular pruning and maintenance.
Propagation
These bonsai trees propagate easily. Make sure you sow the seeds when they are ripe during the Autumn season. They also propagate well with softwood cuttings and air-layering in other seasons of the year.
Pruning and wiring
Acer campestre (Field Maple) Bonsai Trees can be pruned regularly and judiciously as they heal quickly. It is important even to prune them regularly to avoid long internodes. The older branches on these trees tend to become stiff so wiring should be done on the new branches. First complete leaf pruning on these trees, and then follow it with wiring for best results. The most ideal season to prune these Field Maple bonsai trees is in the month of June. With regular maintenance and pruning, the leaves can be kept to under an inch.
Repotting
Maple trees, and specifically Acer campestre (Field Maple) Bonsai trees are very fast growing. Because of this nature, they need to be repotted at a higher frequency than the average bonsai tree. This bonsai species should be repotted at least once in two years. They can be repotted in the spring season before the bud burst. These trees are not fussy about the soil, so they can be potted in regular bonsai soil which include clay, loam, sand, etc.
How to Care for Your Acer campestre (Field Maple) Bonsai?
Acer campestre (Field Maple) Bonsai trees respond well to direct sunlight, with moist soil. These bonsai trees are typically categorized under hardy USDA zones of 5 to 8, so they adapt well in cold temperatures. But smaller bonsai trees need to be frost protected during the winters. The leaves are also susceptible to leaf scorch in the summer and so they should be protected from the sun.
Maple bonsais are fast growing, and due to this they require a lot more maintenance. Regular pruning is very important for this species. Fortunately, Acer campestre (Field Maple) Bonsai trees respond well to judicious pruning and heal quickly.
Another aspect of caring for the Acer campestre (Field Maple) Bonsai is to provide plenty of space for growth. While they adapt well to pots, they grow faster and thicker in open soil. If potted, they need to be repotted in regular intervals of at least 2 years.
Pests and diseases
So far we learnt about all the ways to care for Acer campestre (Field Maple) Bonsai trees. But a very important part of caring for bonsai trees also includes the threats they face from pests and other diseases.
Some pests like leaf stalk borer and petiole borer involve insects that bore into leaf stalks which causes them to shrivel, blacken, and fall off. While the falling off of leaves is concerning, they do not affect the overall health of the tree, as long as the bonsai itself is healthy. Another pest to be weary of are aphids. High numbers of Aphids can cause leaf drops. You can identify Aphid infestation by checking for honey dew on the lower leaves and beneath the tree. Usually, however, you can get rid of Aphids with spraying.
Scales also occasionally cause problems on maple bonsai trees. These insects cause cottony formations on the lower parts of branches. The problem of scales can be controlled with horticultural oil sprays.
Some other problems that can harm the growth of Acer campestre (Field Maple) Bonsai trees are Verticillium Wilting and Girdling roots. Verticillium wilt symptoms would be the death or wilting of branches on the trees. Sometimes it presents itself in the form of stains in the sapwood but not always. If the tree is already infected badly there is no way to save it. But if you see only a light infection, fertilizing and pruning might help save the tree. Girdling roots show similar symptoms to Verticillium wilting.
Most importantly, keeping an eye on the tree at all times and identifying any infestations, stains, or diseases before they become serious is key. As they say, prevention is better than cure.