There is so much to know in the business that it could take years to master everything. You have to know irrigation, pest control, proper pruning and mowing techniques, landscape design, and know the names of a bunch of species of shrubs and trees. I do learn something new everyday in the business. Yesterday I had to treat a ficus hedge for white fly. I was about two hundred feet of hedge. I took about 200 gallons of water mixed with chemical to treat it. It usually takes about three to four weeks for the application to kick in. Now a days you are going to have to treat ficus hedges on a yearly basis to prevent losing your hedge.
You have to know the difference between dryness in your grass, to herbicide burns, to pests in grass, to disease.
The best way to identify disease on your grass in to actually take a blade of grass and check for disease.
This is a close up of what it looks like if you have it. In order to treat it you have to put a fungicide on it. And it will usually heal it.