Phyllanthus tenellus

Longstalked phyllanthus (in the Euphorbiaceae family) is an erect summer annual, although it may occur as a perennial in subtropical environments. Longstalked phyllanthus typically produces a single, erect stem 2 to 3 feet in height, with little branching other than fruiting branches. Leaves are similar to chamberbitter, alternate, oblong in shape, 1/4 to 3/4 inch in length, on short branches, and look similar to compound leaves of some legumes. Plant parts do not exude milky sap when broken. Flowers are greenish-white and round green fruist are produced on the undersides of the lateral branches in the axils of the leaves on short stalks. Seedlings emerge in summer through early autumn but may persist year round in sub-tropical climates. Plants may flower summer through early fall when only a few inches tall, then die after frost. Seeds are forcefully expelled short distances from the fruit when ripe. Longstalked phyllanthus is not well controlled by most preemergence herbicides labeled for use in nursery crops. Emerged plants should be hand weeded when young to prevent seed production and spread. Herbicide efficacy rankings for this species are based on limited experimental data.

Management strategies for longstalked phyllanthus: Longstalked phyllanthus commonly grows in the potting media of container-grown ornamentals and often through drainage holes in containers or through tears in nursery fabric close to irrigation risers. It is a problem in greenhouses and landscapes including both turf areas and landscape beds. As long-stalked phyllanthus germination increases in moist environments, reducing irrigation can be effective.  Group plants according to their water requirements and ensure irrigation systems are well-maintained and are applying irrigation uniformly. Hand pull longstalked phyllanthus as soon as it is seen. Once established, both Phyllanthus species can be difficult to hand weed due to their extensive root systems. Due to the high light requirements needed for germination, mulching can be effective.