In such cases the weeps consist of small-diameter plastic, clay or metal pipes extending through the wall to a layer of porous backfill. Typically, weeps are arranged to direct water which may have entered an assembly from outside back to the outside.
A few of several safe household chemicals to use are vinegar, dishwashing soap and rubbing alcohol, according to an Oregon State University Extension Service publication called Using Home Remedies to Control Garden Pests, (EC 1586). The publication, complete with photos, is available free of charge online.
Horticultural vinegar (20% acetic acid) can be used to spot spray dandelions. Kitchen grade vinegar is not an effective herbicide, its acetic acid concentration is only 5%. The acetic acid concentration needs to be at least 20% to be an effective natural organic weed control.Horticultural vinegar will only kill dandelion foliage-not the taproot-new plants will return from the taproot.Vinegar is also non-selective, take care to spray only weed foliage because it will kill any foliage that you spray-including your grass!orticultural vinegar will only kill dandelion foliage-not the taproot-new plants will return from the taproot. Vinegar is also non-selective, take care to spray only weed foliage because it will kill any foliage that you spray-including your grass!