Suppliers of pulpwood, veneer logs, mine props and railroad crossties who furnish the same to manufacturers, mine operators and railway companies shall be subject to the intangible personal property tax under § 58.1-1100 and shall not be subject to license taxation as merchants, commission merchants or brokers. The word “suppliers” as used in this section means any person, firm or corporation who or which procures such pulpwood, veneer logs, mine props or railroad crossties for such users on a commission basis whether the commission is measured by a percentage of value or of volume.