Cargo ships are designed to carry heavy weights, and without it they ride too high in the water and are unstable.  Ships not laden with enough goods would take on ballast, often in the form of sand or gravel to allow them to safely sail.  In the November 1878 edition of the Torrey Botanical Club, Addison Brown noted that European plants were being transported in the mix of ballast and taking root in Red Hook. 
Much of the ballast was being deposited along the marshy shoreline as landfill, building out more dry land for commercial purposes. Some of it was placed on scows and sailed to other areas of city, likely spreading seeds to the wind along the way.  

An example of a ballast plant that came from Europe to Red Hook, Brooklyn, thrived here when the area was marshland and then immigrated across the country to other marshy areas is the plant Veronica beccabunga, also known as European speedwell or brooklime.

Addison Brown continued his research of ballast plants. At the end of 1880 published his latest findings in the journal of the Torrey Botanical Club but he noted that "most of the grounds of the Gowanus, have been wholly occupied for business uses, so that scarcely anything could be gathered there."   That comment suggests a quick rise in industrialization of the area compared to just a few years prior. 

Four ballast plants listed as growing in the Gowanus area in 1880 but had not been reported in the area before were

• Solanum sisymbriifolium (aka sticky nightshade), spotted in July, and native to South America
• Plantago coronopus, (aka Buck's-horn plantain), spotted in June, and native to Eurasia and North Africa 
• Gillia achillaefolia (aka California gilia), spotted in July and native to California.
• Roubieva Multifida (aka cutleaf goosefoot) native to South America

The origins of these plants species speaks to the global trade that was coming to Red Hooks piers.