I can't get rid of our lava rock, unfortunately, but I'm wondering if anyone can help me figure out how to deal with the weeds? My husband and I just moved into a rental home with a lava rock yard in front. Not our favorite landscaping choice, but the rest of the house is nice. Landlords are not open to letting us change it, and after the first rains of the season (N. California -- East Bay) a billion weeds sprung up. I have spent a couple sessions trying to pull them by hand, but it is really impossible to get them up through those rocks (and there is some sort of black plastic tarp underneath, that is not in good shape). Can anyone offer suggestions? I am almost 7 months pregnant, so I can't really get down there to do too much more hand weeding right now, and I'd rather not use anything horribly toxic. Landlords expect us to keep up the landscaping appearance, so we need to do something soon. Thank you!!

Not all sumacs are alike, not all sumacs spread (the rope-like roots of those that do are called "ryhzomes"), and those that spread are a gardener's nightmare. I have only come up with one proven solution to getting rid of them, and that is by digging up and removing every single inch of rhyzomes by hand. This has been proven in Eastern Canada and the USA where sumacs are an invasive species. Roundup only kills the plant above ground; ditto for burning. Cutting (eg using a lawnmower) encourages spreading. Rototilling spreads the pieces of rhyzomes around where they will take root happily. There IS a herbicide that must be applied to the rhyzomes that will kill them, but since you have to dig them up to do so, you might as well just remove them. That herbicide is only legal for use in Canada by trained and licenced users, not the average gardener. It can be obtained in the USA, but as already said, you have to dig up the rhyzomes to paint them with it, so you might as well just remove them and not bother with the applicating of the herbicide. If you don't remove the parent plants, they will of course send out new babies to replace all you've dug up… Since the rhyzomes can go more than 2' deep, I doubt a root barrier would stop the spread. I am personally dealing with this exact situation right now. It is said that it takes 3 years of careful digging (removing bits you missed the previous year), to remove everything. So this is not a quick and easy project you must undertake. People will be happy to dish out free advice on this, when they see you on yours hands and knees digging, but virtually no one has any advice that is worth trying. Kneel and dig is your ONLY viable option. For three thorough, consecutive years. Tough if you have arthritis anywhere… All the best. In the picture below, I have dug up rhyzomes on the right side, just to the left of the Maple tree in the middle. The orange flags indicate where I left off, and areas to be watched for regrowth, or rhyzomes that go deeper than 2'. There are 2 adult sumacs on the left of the house. The original parent plants died long ago, and I eventually cut them down. So I'm sure the existing 2 adults are now sending out lots of rhyzomes… There are sproutings in the next door neighbour's property, so unless I put in a root barrier, and it WORKS, the rhyzomes with just come back from his property. And no, he won't bother digging them up. The lawnmower technique is the most he'll do… file://localhost/Volumes/LEXAR/DCIM/101ND300/DTC_8768.JPG

That moss is more than likely growing there because of a soil problem, most likely low organic matter levels in the soil, as well as low sunlight that all grasses need to grow. Start working on eliminating the moss be getting a good, reliable soil test done. Ialk with the people at your counties Ohio State University Cooperative Extension Service about having that done and also dig in with these simple soil tests. 1) Structure. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. A good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top. Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up. 3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart. 4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer your soil will smell. 5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy. The results of these tests can guide you in making corrections to the soil so other types of plants have a better chance of growing there. Here is a link that might be useful: OSU CES

I have tried in the past when I saw this to spray with neem oil but everytime they are on multiple leaves the plant will die. I just had a beautiful 3 year old serrano/tabasco? hybrid that succumbed to this whitefly problem. I know you are supposed to wipe down / remove and then spray every leaf and stem where these whiteflies are but with a plant like my Serrano there would have to have been thousands of tiny leaves. Impossible to do every leaf every 2-3 days until they were gone and then hope they don't return from other plants or neighbors that have them as well. It is odd as this year I have seen these infestations around my area in many locations. Not sure why this year is worse than most. Also I do see lacewings but the whitefly seems to laugh at them as the lacewings arent putting a dent in the whitefly population. I also have citrus trees and these whitefly and blackfly are intertwined throughout those trees as well.