Here is information on toxicity of pokeweed/Phytolacca americana .  Please read this carefully before you start.  https://www.oardc.ohio-state.edu/weedguide/single_weed.php?id=112

"Toxicity:

All parts of common pokeweed are toxic to humans, pets and livestock. Roots are the most poisonous, leaves and stems are intermediate in toxicity (toxicity increases with maturity), and berries are the least toxic. Since common pokeweed is not very palatable, most animals avoid eating it unless little else is available, or if it is in contaminated hay. Horses, sheep and cattle have been poisoned by eating fresh leaves or green fodder, and pigs have been poisoned by eating the roots. Children are most frequently poisoned by eating raw berries. Infants are especially sensitive and have died from eating only a few raw berries. Although boiled young shoots have been eaten as greens and berries cooked in pie, ingestion of any part of the plant cannot be recommended. Adults have been poisoned, sometimes fatally, by eating improperly prepared leaves and shoots, especially if part of the root is harvested with the shoot, and by mistaking the root for an edible tuber. Research with humans has also shown that common pokeweed can cause mutations (possibly leading to cancer) and birth defects. Since the juice of pokeweed can be absorbed through the skin, contact of plant parts with bare skin should be avoided. Symptoms of poisoning from common pokeweed include a burning sensation in the mouth, salivation, gastrointestinal cramps, vomiting and bloody diarrhea. Most people and animals recover within 1 to 2 days if only small quantities are eaten. If large quantities are consumed, more severe symptoms can occur, such as anemia, altered heart rate and respiration, convulsions and death from respiratory failure. The primary toxic compounds are thought to be oxalic acid, saponins (phytolaccotoxin and phytolaccigenin) and an alkaloid (phytolaccin)."

"Pokeweed is a native plant that produces purple berries in the late summer/fall that birds relish and spread. It is aggressive not invasive. It has a huge tuber-like root that stores a lot of carbs. If there are seeds in the soil, you will be battling this and you will have to stay on top of it as soon as you see new growth. There are no easy answers.

     For new plants - Exhaust the root system of new plants. Just keep cutting new shoots back as soon as they appear until the roots don't have enough energy to produce new shoots. You can also manually remove plants prior to flower formation and seed production.

     Or you can spray new foliage with a systemic herbicide that will travel down and kill the root. Glyphosate is the ingredient to look for on the herbicide label. As soon as you see new growth, you will have to spray. Follow label directions for control.[Whenever applying chemical controls, always follow label directions.]

Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension horticultural consultants. For more information on a variety of gardening and pest topics visit our website http://extension.umd.edu/hgic.