My backyard has five feet of land which is full of grass. Recently I used vinegar on the grass per your tips on your website. The problem is that I don't get enough sunlight in my backyard. Will the vinegar still kill the grass? How often do I need to spray the grass with vinegar?
The acid in the vinegar is what kills the plant more than anything. If it is a tough plant, it may take several applications. I would apply it every few days until they are dead. If there are no plants in that area that you wish to save, I would recommend boiling water. Pouring this on the plants will kill them instantly.
I was told most weed trees will die if I cut down below the crown as long as they are young enough to get my pruners around them. Is this true?
Not necessarily. Many will only produce additional suckers below the cut. Pulling or digging them up is often just as easy and all of the roots will be obtained this way. This article will provide additional information to help you will this: https://www.gardeningknowhow.com/ornamental/trees/tgen/weed-trees.htm
Does orange gel and highly acidic vinegar help to kill weeds?
Yes, the acid in the vinegar helps to kill weeds, but be careful, it will affect any plant it is used on.
Is there a spray I can use to rid a play area of goat head sticker grass and other weeds/grasses, including killing the seeds?
Round-up is pretty all inclusive when it comes to killing every part of a plant. If you are looking for something more organic, boiled water will do the same. But be aware, both of these will kill any plant that it comes in contact with.
I purchased a house with extensive gardens that have been neglected for two years. It's my first house and first garden, so I am truly a novice. I got advice from an experienced gardener in the fall to cut back everything and see what grows in the spring, then pull out what seems to be weeds. Now I have two flower beds that have more grass growing than plants. Is there a way to address the weeds/grass other than pulling each out by hand?
You can try Round-up with a spray shield to direct the spray. This site will explain how to make a spray shield:
http://www.thisgardenisillegal.com/2006/05/how-to-make-soda-bottle-weed-killer.html
I love the suggestion of using vinegar to kill grass. I would like to put native plants in (I live in the NW) when the grass has died and been cleared away. Will the soil support these plants? If so, what needs to be done to the area prior to planting?
Vinegar poses no ill effects to the soil. Therefore, there is no need to do anything other than prepare the area for planting, which should be amended with organic matter if at all possible. Also, research the plants that thrive in your area and choose these types of plants or at least those with similar growing requirements.
These articles should also help:
https://www.gardeningknowhow.com/special/spaces/native-plant-environments.htm
https://www.gardeningknowhow.com/special/spaces/gardening-with-native-plants.htm
I have two kinds of weeds together in my yard and have used fertilizer plus week killer but it comes back every year. Is there a natural liquid that I can mix in my kitchen that will kill these weeds?
Generally, the best way to get rid of chickweed is through manual pulling or the use of an herbicide. The following article can help:
https://www.gardeningknowhow.com/problems/weeds/how-to-kill-chickweed-best-way-to-kill-chickweed.htm
For a more earth-friendly approach, you could try some of the tips in this article: https://www.gardeningknowhow.com/special/organic/homemade-pet-friendly-weed-killer.htm