Blackspot is a fungus that causes black spots about 1/16 to 1/2 inches in diameter to form on the leaves and sometimes stems. The infected leaves later turn yellow around the spots and eventually fall from the plant. In bad cases, blackspot can severely defoliate a rose bush. The conditions that promote blackspot are wet leaves, splashing water and warm temperatures. Here are some ways to combat blackspot. Most of these methods also apply to preventing and treating powdery mildew.

This is an indication of a fungal infection. Fungal infections are usually the result of warm temperatures, high humidity and low light levels. Treat the plants with a systemic fungicide such as Phyton 27. See similar questions...

This is a disease called black spot. It is a common and disfiguring disease of roses. Fungicides are more effective when applied as a preventative disease control. We suggest alternating between different fungicides to reduce any chance of disease resistance. Roses will need to be sprayed once every 2-3 weeks from May through September to keep black spot and possibly other problems under control. See our staff for guidance and specific control recommendations. See similar questions...

Black spots are endemic in a number of varieties of orchids, most notably those in the Oncidium or Oncidium family intergenerics. These spots are not a sign of disease. They cannot be removed, and will not spread from plant to plant. You can think of them as freckles. These spots are generally small and dry. If, however, your plant suddenly develops large black spots, particularly if they are moist, this could be a sign of disease. See similar questions...

This is generally a leaf rot caused by types of fungi that are commonly classified as Cercospora or Colletotrichum. Many times this rot will start out as yellow spots, gradually turning to a brown or black color. Note that certain plants such as most Oncidium hybrids often get several small black spots on the leaves due to the sun. In this case it is natural spotting and will not harm the plant. See similar questions...

A fungus called Blackspot. It is a common disease in our humid summers. Spraying a fungicide and increasing sun and circulation helps reduce this disease. See similar questions...

That's a fungal leaf spot called black spot. Some varieties are highly susceptible to it and will require weekly spraying with a systemic insecticide just to exist. Without the protection the plants grow stemmy and weak. Other types, including the recognized EarthKind roses identified by Texas A&M, are far less prone to the disease and can exist without heroic spraying. See similar questions...

Black spots on flowers are usually caused by Botrytris, a fungus. The problem is caused by poor air circulation and too much moisture. The remedy is to increase air circulation and reduce the humidity. See similar questions...

Leaf cutter bees cut semi-circle shaped holes in the leaves of roses. They pose no real threat to rose health, but they drive exhibitors crazy. See similar questions...

The black spots are a fungus disease called Tar Spot. It infects Norway maple (including all of the horticultural forms such as "Crimson King"), Silver maple and Freeman's maple. The disease infects leaves late in the season and has little impact on the overall health of the tree. The disease is already widespread and sanitation (leaf removal) is not effective in reducing the infestation level for the following year, so let the leaves decay under the trees to at least improve the soil health. See similar questions...

Lance Harringtion wrote "I have hard water spots on my orchids leaves, can you tell me how to remove them without hurting the plant. I have tried vinegar and water." Here is a list of possible ways to remove the hard water spots. Thanks to all the members of OLD for their contributions on this subject. This makes the leaves clean and shiny. It also lasts a long time. This will not hurt the leaves the way general "leaf shine" type products may do. See similar questions...

We'll dealing with a two-strikes against situation. Black is dominant, but is diluted by Dun, and modified by Agouti This means both parents have to carry black or be black. Then you have to get the spots, which, as discussed earlier, you are getting 50/50 chances. If black spotted animals are only bred to gray-dun, then you have taken away the necessary factor to match up the black. See similar questions...

Fretting is a common problem with Tin Plating. This is surface damage created when there is relative motions and strong contacts between parts, usually during shipping and handling. The tin plating shows black or worn spots caused by rubbed or scratched by another part. This oxide does not effect the parts functionally. They are still solderable. A way to eliminate fretting is by changing the type of packaging. (Layer packing or plastic trays are recommended) - Metal Finishing Guidebook 1997 See similar questions...

Those “water spots” on dishes are precipitates, or minerals in the water that are left behind when water evaporates. To prevent this, use a rinsing agent such as JetDry, which improves the sheeting action of water and helps to prevent spotting. Also, be sure to use the proper amount of dishwashing detergent. Using too little may not get your dishes clean, and using too much can cause etching, which is tiny scratches on the surface of the glass that cannot be removed. See similar questions...

Your rose leaves are being eaten by Christmas beetles. They live in the soil by day and appear at night to feed. Spray the foliage and the soil surface with EFEKTO KARBASPRAY - dissolve 15g in 10 litres of water. See similar questions...

The black on the bottom of your tomatoes is called "blossom end rot." It is caused by a lack of calcium and other ingredients from the potting mix. Adding 2 cups of hydrated lime to the potting mix before planting as in the instructions can help prevent the blossom end rot from forming. In the event the blossom end rot still presents itself mix 1/4 cup of hydrated lime with one gallon of water and add that to the resevior the next time you fill your Earthbox with water. See similar questions...

They are probably pet stains, but can also be water. The fact is that nobody can tell you if sanding will remove them until you physically try with a professional machine. See similar questions...

These are the cosmetic blemishes in the image intensifier, which do not affect the performance or reliability of a night vision device. A certain number of such spots of varying sizes are inherent in the manufacturing processes. They can also be dirt or debris between the lenses, which should be removed by careful cleaning if the system is designed with interchangeable optics. See similar questions...

Probably not. These are most likely caused by water and there is resultant wood damage. Do the wet paper towel test and see if the result will be satisfactory. See similar questions...