How many kinds of trees are there in the world?

Shrubs: Hibiscus Hibiscus, bougainvillea bougainvillea/ Rhododendron, Oriental golden phoenix, Milan, Murraya murraya, Dragon Boat Flower, Hydrangea, Coffee, Gardenia, Lilac, Jasmine, African Jasmine, Dog Tooth Flower, Lantana, Yellow Cicadas, Nerium oleander, Egg Flower, Osmanthus fragrans, Ligustrum microphyllum and upside down Admiralty.

Trees: peach blossom, Davidia involucrata, kapok, Java kapok, bauhinia, bauhinia, rain tree, acacia, Erythrina, Magnolia grandiflora, cycad and Lagerstroemia indica.