Q.Olive trees
How many gallons of water per week should I water my 12 foot olive trees planted 2 years ago? The leaves turn yellow and drop. Also, when they were planted, the planters were teeming with tiny ants.
Here are some links that will help you with watering and care.
http://ucmanagedrought.ucdavis.edu/Agriculture/Crop_Irrigation_Strategies/Olives/
https://www.gardeningknowhow.com/edible/fruits/olive/olive-tree-care-information.htm
https://www.gardeningknowhow.com/edible/fruits/olive/pruning-olive-trees.htm
https://www.gardeningknowhow.com/ornamental/shrubs/elaeagnus/russian-olive-information.htm