One plastic sheet of 15cm x 5cm plenty with Gamer's Grass tufts. Tufts are 4mm tall.
Just pop-out the tufts from the sheet of plastic and glue them to your models.
About 100 smaller tufts per sheet.
Standard sized tufts, they come about 70 of them in one sheet.
Wild ''sized'' tufts are tufts in a wide variety of shapes and sizes.