<P> They are extremely important food for numerous species of birds, and also are eaten by other wild animals . In the autumn and early winter the fruits are hard and apparently unpalatable . After being frozen or frosted several times, the fruits soften, and become milder in taste . During winter storms, birds often take refuge in hollies, which provide shelter, protection from predators (by the spiny leaves), and food . The flowers are sometimes eaten by the larva of the double - striped pug moth (Gymnoscelis rufifasciata). Other Lepidoptera whose larvae feed on holly include Bucculatrix ilecella, which feeds exclusively on hollies, and The Engrailed (Ectropis crepuscularia). </P> <P> Holly can contain caffeic acid, caffeoyl derivatives, caffeoylshikimic acid, chlorogenic acid, feruloylquinic acid, quercetin, quinic acid, kaempferol, tannins, rutin, caffeine, and theobromine . </P> <P> Holly berries can cause vomiting and diarrhea . They are especially dangerous in cases involving accidental consumption by children attracted to the bright red berries . Ingestion of over 20 berries may be fatal to children . </P> <P> Holly leaves, if eaten, might cause diarrhea, nausea, vomiting, and stomach and intestinal problems . </P>

Are the berries on a holly tree poisonous