The Content Of The Article:
- What exactly is the rubber flow?
- Damage and effects on the affected tree
- Rubber flow has many causes
- Pests and diseases
- Unfavorable culture conditions
- Wrong / inadequate care
- Injuries of various kinds
- Treat rubber flow effectively - it does not work without pruning
- Prevention is better than cure
- Pay attention to the right location when planting
- Plant a few diseases susceptible varieties
- Cut fruit trees properly and provide wounds
- Endangered trees in autumn lime
It is mainly sweet cherry, peach and apricot endangered, with many causes are responsible for the phenomenon. Rubber flow occurs mainly on cuts and other injuries of the tree, but also in apparently undamaged areas on the bark. This tears up and thus offers further pathogens a gateway. Pests can increase the rubber flux, but it is not primarily a disease caused by fungi or bacteria. Instead, the rubber flow is a physiological disorder of the tree, which can lead to the death of whole branches and a strong impairment of the harvest.
What exactly is the rubber flow?The gum occurs mainly in young or very old trees - ergo copies that react from the outset to incorrect care or poor growth conditions more sensitive than trees that are at the zenith of their vitality. Even the layman clearly recognizes an outbreak of the disease from the resin-like outgrowths that emerge from the branches or even the trunk. This resin is similar in color and consistency to that of the conifers, but has a very different chemical composition. It is mostly about dissolved plant tissue, whereby about the wood of the affected tree is liquefied and broken down into various sugar compounds and acids. Rubber flow occurs when the metabolism of the tree is disturbed, the causes are very diverse.
Damage and effects on the affected treeMainly injured areas of the bark, but also superficially healthy appearing parts of the tree may be affected by the rubber flow. After all, injuries can not always be recognized as such at first sight: in many cases, the disorder is the result of minute tears in the bark, caused by tensions in the frost, or eating traces of pests such as the bark beetle or the bark winder. At the injured point under the bark, a source of illness develops, in which the discharge forms and finally emerges visibly from within.
Unfortunately, the gelatinous mass can not only spread outwards but also inwards and, for example, block important pathways. As a result, the affected part of the tree is no longer sufficiently supplied with water and nutrients, so that he eventually dies. As a rule, only individual shoots or branches are initially affected, but the worst case scenario is that the disease can spread to the whole tree and ultimately kill it altogether. In rare cases, the rubber flow also occurs on the fruits.
Rubber flow has many causes
The gumose is not indicative of a particular disease, but rather as a feature of a generally weakened tree. One of the main causes is considered heavy, wet soils. Anything else that strains the tree can also cause or intensify the rubber flow: wetness, frost, bark injuries or inharmonious nutrient supply are also among the reasons.
Pests and diseasesVery diverse are the parasitic causes for the emergence of rubber flow. Here, fungal and bacterial diseases mainly of the bark, but also different animal pests play an inglorious role. Most often, the disorder is associated with the frequent occurrence of peach ragweed, monilia-tip drought, shotgun disease or Valsa disease.
leaf curlIn curling disease, the leaves curl strongly, dry up and eventually fall off. The cause is a fungus that overwinters on the branches and infects the sprouting leaves in spring - especially in rainy weather. Affected shoot tips and leaves should be removed quickly. The use of pesticides is only successful if they are applied at the right time - at bud swelling. It is best to choose a peach variety that is resistant to ragweed.
Fungus disease MoniliaThe fungal disease Monilia occurs in two different forms: as top drought and as fruit rot. In the lace drought or branch monilia often wither first flowers and shoot tips, and finally the leaves. Often you can see gummy drops on infested shoots, later forms a yellowish to gray mushroom lawn. Carefully cut affected shoots back into healthy wood and carefully remove dried-up flower clusters as well as fruit mummies from tree and soil. Approved pesticides are available for the treatment of sour cherry, sweet cherry and plum.
Shotgun diseaseThe shotgun disease occurs on plum, cherries, peach and apricot.On the leaves show soon after budding numerous reddish to brown spots that break out later. As a result, the foliage has a shotgun hole perforated. The buds, flowers, fruits and shoots may have sunken, partly red-bordered spots. However, some stone fruit varieties are considered to be low prone and should therefore be preferred at planting.
ValsakrankheitThere are also variety differences in the risk of Valsa disease on cherries, plums and apricots, which is favored by heavy, moist soils. It manifests itself by cancerous bark growths with dark, wart-like points (similar to a "toad skin") as well as rubbery drops. Withered leaves wither leaves and fruits. Affected parts of the tree should be cut out generously. If the trunk is affected, usually only the removal of the tree helps.
RindenwicklerIn addition to the mentioned pathogens, pests such as the bark winder can cause a gum disease. It is a butterfly species with the scientific name of Enarmonia formosana, whose caterpillars feed on the bark of various fruit trees and thus can cause severe damage.
Unfavorable culture conditions
The onset of rubber flow, but even the infestation with various pathogens and / or pests can often be attributed to unfavorable culture conditions and concomitant weakening of the affected tree. Especially heavy, waterlogged soils damage the trees growing on them, so that they are no longer able to defend themselves against attackers. But also sandy soils are not suitable for the culture of stone fruit, instead you should plant the trees in a deep, humus- and nutrient-rich and slightly calcareous soil. If necessary, make sure to improve the soil, for example by adding plenty of compost. Even a little protected, late frost-prone location can be dangerous especially sweet cherries and peaches and apricots.
Wrong / inadequate careFurthermore, poor fertilization and thus nutrition of the tree, improper pruning and incorrect refining (for example on an unsuitable surface) can lead to rubber flow. Health, growth and yield can be improved if you have fruit trees
- provide compost and / or potash fertilizer in the spring
- fertilize balanced and not nitrogen-stressed
- mulching after the last late frosts
- in case of severe drought (especially during fruit development!)
- Protect young trees and early flowers in late frosts with fleece
- Finishing fruit trees regularly, preferably after harvest
Injuries of various kindsAlso, be sure to avoid any type of injury, such as excessive or improper pruning or late frost, or to provide immediate proper care. Many stone fruits are quite sensitive to frost and need winter protection. But even if they are frost hardy, a frost that sets in late in the spring can have grave consequences: The tree, which is already "fully in the juice", gets the finest cracks in the bark due to the strong cold, which in turn leads to weakening and thus a cause can be for rubber flow.
Treat rubber flow effectively - it does not work without pruningOn trees prone to rubber flow, strong shoots are best cut back on cones. While the gardener should generally not leave any cones or stubs, there are a few exceptions for stone fruit (and berry fruit). Here, when cutting, pruning and deflecting strong shoots, it is best to leave pins about 20 centimeters long over the interface. The rubber flow then forms on the pin, which dies over time and can be removed, but does not damage the remaining drive part. In addition, stone fruit endangered by rubber should be pruned, preferably in summer, directly after harvesting. A cut at this time promotes rapid wound healing and slows growth. A winter cut, however, should be avoided as far as possible.
Prevention is better than cureRubber flow must always be treated as quickly as possible, otherwise large parts of the affected tree can die off. Therefore, carry out regular checks and look not only for signs of gum disease, but also for a possible fungal, bacterial or viral infection or pest infestation. You should also pay close attention to the care and welfare of the fruit trees and take further preventative measures.
Pay attention to the right location when planting
So the best prevention is to plant fruit trees right from the start in a suitable location for them.Cherry and plum trees in particular thrive on neutral to alkaline soils, and experience much better results than acidic ones, making them less susceptible to plant diseases. Peaches, nectarines and apricots thrive best where it is warm, sunny and protected - it is not for nothing that these frost-sensitive fruit varieties have become established in Germany, especially in the winegrowing regions. On the other hand, if you live in a climatically less favorable region, you can ensure suitable frost protection during the winter months and especially in the case of impending late frost in the spring.
Plant a few diseases susceptible varietiesIn addition to a suitable location you should plant especially varieties that are less sensitive or even resistant to many rubber-causing diseases. This already eliminates a common cause from the outset. In the overview below we have compiled some recommendable, little disease-susceptible stone fruit varieties for you.
Robust plum varieties for the garden
- 'Hanita': also for rough situations, very little schaaraanfällig
- 'Bühler Frühzwetschge': little susceptible to sharka and other diseases
- 'Jojo': resistant to scarlet fever
- 'Katinka': little schaaraanfällig
- 'Ontariopflaume': little schaaraanfällig
- 'Opal': little schaaraanfällig
- 'The Czar': very sturdy, with little susceptibility to scars
- 'Bellamira': little susceptible to sharka and other diseases
- 'Mirabelle of Nancy': little prone to sharka and other diseases
Robust sweet cherries for the garden
- 'Burlat': very robust, madenfrei
- 'Regina': very robust, strong
- 'Kordia': low site claims
Robust sour cherries for the gardenWhen selecting a suitable sour cherry variety, you should pay particular attention to the taste preferences in particular to the resistance to the Monilia lace drought. For example, the popular black moray eels are considered very susceptible to monilia. On the other hand, varieties such as 'Morellenfeuer' and 'Morina', resistant even to 'Ludwig Frühhe' and 'Safir', are less susceptible.
Robust peach varieties for the gardenIn general, peaches are very sensitive and especially prone to cramp disease. On the other hand, varieties such as 'Benedicte', 'Kernechter vom Vorgebirge' (also known by the name 'Roter Ellerstädter'), 'Revita' or 'Roter Weinberg peach' are considered moderately susceptible to disease.
Cut fruit trees properly and provide wounds
In the main growing season, the tree has the most energy, the cell formation is more active and the wounds overgrow better and faster than in winter. In addition, if the foliage roof is fully unfolded, no more juice drips out than the cuts. For these reasons pruning is to be preferred, especially after harvesting. In addition, the right wound treatment after the cut is very important: Smaller wounds usually heal by themselves, but as soon as they are larger than a two-euro piece, a follow-up treatment makes sense. To do this, cut the wound edges with a sharp knife and spread with a suitable wound sealant. Treated wounds begin to swell rapidly from the edge; new cells are formed from the Cambrian, the dividing tissue located beneath the cortex.
Tip: But not only in connection with the cut, careful wound treatment is important. Damage to the trunk and branches caused by frost, fruit tree creeping, slitting a branch or other causes should also be treated quickly. In such cases, the edges of the wound will be resected with a sharp knife in the spring or, as soon as the damage can be seen, and with a wound closure agent. For cancer and frost wounds, however, the smooth cutting of the wound edges is not enough. In this case, cancer sites and frost plates have to be cut out thoroughly down to the healthy wood.
Endangered trees in autumn limeYou can avoid cold damage and damage caused by pests by limescale your fruit trees in autumn. Mix lime in powder form with water until creamy and spread the mixture with a thick brush on the tree trunk. The white paint reflects the sunlight and thus reduces excessive temperature fluctuations in the wood - with the result that fewer frost cracks occur.
The so-called Gummifluss or Gummose is not a plant disease in the true sense, but rather as a symptom of a sick or weakened tree to see. The causes of this phenomenon are very diverse: pathogens can be pathogens and pests as well as unfavorable site and growth conditions, incorrect or inadequate care, as well as frost damage and other injuries. Affected trees should be treated promptly, as the resinous, usually colorless to amber-colored discharge clogs the pathways and can lead to the death of large parts of the tree. Basically, almost all deciduous trees can be infested, but usually the gum is more common in stone fruit of the genus Prunus.