I have a white powder substance on two of my shrubs in my front yard and the plants are slowly dying. One shrub has more and more dead branches and this white powder is all over the branches. What is this and how can I fix it?
That is powdery mildew. These articles will help:
https://www.gardeningknowhow.com/problems/get-the-cure-for-powdery-mildew.htm
https://www.gardeningknowhow.com/plant-problems/disease/powdery-mildew-homemade-and-organic-remedies.htm
Our hedge and 2 pyramid trees are looking terrible and a neighbour parks and runs his van every morning directly beside them (in winter it idles for at least 20 minutes) while everything else not in the vicinity of his vehicle is doing great. Could this be the cause of them doing badly? Prior to his moving in, they were great.
The property next door to me is a rental property. Over the years there have been renters who leave their vehicle idling (the driverway for the property runs along our fence line, and over the years I have had damage to azaleas, dogwood tree and pine tree from exhaust. My conclusion is plants do not like carbon monoxide.
I could find little information but one source states that exhaust makes it impossible for plants to photosynthesize, (convert light to energy.). I would hate to confront him only to find out the plants have a totally different problem. HOpe you find a better answer.............
I need something that will kill shrubs and root killer for all bushes and tree stumps.
Roundup is the normal herbicide used for this. Apply liberally and at full strength. For root stumps producing suckers, cut the suckers off and apply Roundup to the open wounds on the stump.
I have some tiny white bugs on shrubs that are killing leaves and coating stems. What product will kill them?
I would give neem oil a try. It is safe to use but will take care of most insect pests, leaving the beneficial ones alone. It is also a great fungicide, should any after effects from the insects cause any additional problems. Here is more info: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
I have shrubs around the house and lately they have on the leaves and stems a white powered stuff. What can I do to control this its killing the stems and roots?
I think it may be powdery mildew. These articles will help you:
https://www.gardeningknowhow.com/plant-problems/disease/powdery-mildew-homemade-and-organic-remedies.htm
https://www.gardeningknowhow.com/plant-problems/disease/get-the-cure-for-powdery-mildew.htm
I have many shrubs and small trees that I would like to kill. Some are around a chain-link fence and have become part of the fence so they cannot be cut at ground level. Others I have cut at ground level, but they just keep growing back around the stumps. Any suggestions?
You're most likely dealing with sucker growth. Cut the suckers and paint the fresh cuts with undiluted Round-up. This will get into the remaining root system and kill the roots. It may take a month or so, but it will work. Perhaps this article may be of some help to you as well: https://www.gardeningknowhow.com/ornamental/trees/tgen/how-to-kill-a-tree-killing-trees-in-your-garden.htm
I have shrubs that the leaves are turning either black and wilting or yellow and are losing leaves.
These articles should help with that: https://www.gardeningknowhow.com/plant-problems/environmental/under-watering.htm
https://www.gardeningknowhow.com/plant-problems/environmental/signs-of-plants-affected-by-too-much-water.htm