Aquacide Blog — pondweed identification

ALLIGATORWEED (alternanthera philoxeroides) was first reported in the U.S. in 1897.  It originated in South America and was probably introduced in the U.S. through ballast water.  It is now also considered an invasive weed in Australia, China, New Zealand and Thailand. Alligatorweed has long elliptical leaves that branch opposite on hollow stems that stand 4 feet high.  It has a whitish papery ball-shaped flower that closely resembles clover.  The flowers are located on spikelets that rise from the leaf base. Alligatorweed spreads by seed and fragmentation. When Alligatorweed invades waterways it can reduce flow, prevent light penetration and deplete oxygen due...

Q---I’m considering buying a property with a spring-fed pond.  Before I sign on the dotted line, what kind of maintenance considerations should I be aware of? A---Spring-fed ponds are relatively rare.  Water flows out of spring-fed ponds at all times, not just after heavy rains.  Many people mistakenly think they have spring-fed ponds.   During construction, water gushed into the dug pond area from what was assumed to be instead what they saw was ground water flowing into the hole from veins of water–bearing sand or gravel.  If, however, water is discharged through a spillway, it is indeed a spring-fed pond....

Duckweed and Watermeal are free floating pond weeds that are found in wetlands and nutrient rich stagnant water. They are often mistaken for algae. Pond weed identification can be done by recognizing its small, round floating “frond” or leaf. Duckweed frond has hanging roots and is roughly the diameter of a pencil eraser. Watermeal has no roots and looks like floating grass seed about the size of a pin-head. Duckweed and Watermeal reproduce by budding on the margin or base of the frond. Each frond can only do this a limited number of times before dying. Both survive freezing and...

While many people jump in the lake to keep cool, living life underwater isn’t always enough to protect fish from the heat. Many people throughout the US have noticed fish struggling at the water surface and washing up onto their shore.  This is due to the heat wave that has hovered over the Midwest over the past few weeks. Fish kills are actually common and do happen every summer, its part of the natural cycle.  Oxygen levels have reached an all time low.  Low oxygen levels combined with high water temperatures cause fish kills that sometimes have people convinced their...

Brazilian Elodea (egeria densa) was introduced to this country about 100 years ago.  It was an attractive oxygen producing plant primarily sold as an aquarium plant.  It can now be found in 40 States including Hawaii. It is an aggressive lake weed, very similar to both American Elodea and Hydrilla.  All three are submersed and rooted to the lake bottom.  Leaves of Brazilian Elodea have minute teeth not visible by the naked eye.   It spreads primarily by floating fragments that simply re-root.  It does not use seeds or tubers.  Stems are long and slender and rarely branch.  Each leaf is...