I have entered a custom pesticide to my product database, but in my Pesticide Usage Report, no active substances are listed for this pesticide. Why?

If you have added a pesticide as a custom item, you will need to manually enter all active substances and their percentage for that product. You can do this while registering a new product, or by editing the item details. Under "Resources" → "Manage Items," locate the item you added to the product database, then select the Options icon and "Edit details" to adjust active substances.