Jane magnolia trees are among the hardiest magnolias, according to the U.S. Department of Agriculture. However, they can fall prey to infections and disease just like other trees, and knowing how to react to these problems can dramatically improve your chances of saving your Jane magnolia if and when it does fall "under the weather." There are several options for treatments for a Jane magnolia tree, some of which involve chemical applications and some of which are entirely "green."
In the event of a fungal infection, sterile pruning will help you get the infection under control without spreading it. Use rubbing alcohol to wipe down your clippers after every cut to prevent yourself from spreading the fungus to other areas of the tree, and be sure to burn or bag all removed plant materials rather than allowing them to fall to the ground. Sterile pruning is the first line of defense when it comes to leaf spots, blights and scorches, according to the University of Missouri Extension.
Raking and Mulch Removal
Fungal infections and diseases often overwinter in the plant debris and mulch underneath Jane magnolia trees. Whether you have already noticed signs of trouble on your tree or are just trying to prevent health issues for your Jane magnolia, removing plant debris and old mulch from under the tree can help prevent the growth and propagation of fungi. If your tree has leaf spots or wilt, then this is a necessary part of treatment to prevent the disease from simply reinfecting the tree once you have removed impacted foliage.
Use of Pesticides
If your Jane magnolia has insect infestations, you may need to resort to insecticides to keep them off of your tree. Additionally, fungal infections often need the additional weight of a fungicide on them to prevent them from spreading. If you have already tried sterile pruning and mulch removal and you still have been unable to check your tree's disease, then using a fungicide or a bactericide may help push the balance in your tree's favor permanently. Be sure to consult a professional before applying pesticides to your Jane magnolia, since not all chemical options are legal in all areas. If you have ever had verticillium wilt in your yard, then a preventative fumigation of the soil with a fungicide can help your tree resist these organisms, which live in the soil and are very difficult to get rid of naturally without replacing the soil in an area.