Callitriche Stagnalis (Starwort) NATIVE Oxygenating Pond Plant. Callitriche Stagnalis is an excellent British, native, wild submerged pond plant. As a water star wort, it is submerged and part terrestrial (grows on land and in water). It is an excellent pond plant for oxygenating and maintaining clean and healthy pond water and provides a protected environment for small fish and wildlife. Posting: Monday-Thursday Except Bank Holidays All Plants are posted FIRST CLASS Plants are packed to last 7 days. Supplier of plants: oxygenators, reeds, iris, water lilies, bog gardens, wildlife ponds, natural ponds, lakes, floating plants, deep water plants, marginals, native british and tropical.