This industry comprises establishments primarily engaged in the merchant wholesale distribution of flowers, florists' supplies, and/or nursery stock (except plant seeds and plant bulbs). Cross-References. Establishments primarily engaged in-- ? Merchant wholesale distribution of cut Christmas trees--are classified in Industry 424990, Other Miscellaneous Nondurable Goods Merchant Wholesalers; and ? Merchant wholesale distribution of plant seeds and plant bulbs--are classified in Industry 424910, Farm Supplies Merchant Wholesalers.