Question
my kangaroo paw fern has brown bumps on the underside of the leaves.  is this a pest?  if not a pest, what is it.

thank you

Answer
Hi Barbara,
   Yes, it is very likely that the brown bumps you are seeing are Scale insects.
Scale insects are black, brown or tan, somewhat flat, oval shaped insects that are covered by a hard shell. Adult scales are stationary. Immature scales (called crawlers) emerge from eggs deposited under the adult females protective shell. Once crawlers establish a feeding site, they begin to secrete the hardened covering over their body. Adult Scale are a problem to control because their shell protects them from pesticides. Pesticides and soap sprays are only effective on crawlers. If there are only a few Scales, they can be picked off by hand. A Q-tip dipped in alcohol works well to pick off Scale insects. After picking off the Scale you see, you can spray the plant with a mix of soapy water and alcohol to get any crawlers that escaped your notice.
Check the plant every few days, picking off any scales you find and spraying for those you don't. Scale are also often found in crevices, folds and creases on both the plant's leaves and stems.

By far the best way to control Scale is by using a systemic insecticide. In cases of a heavy infestation, a systemic is the only effective means of control.
A systemic insecticide is a insecticide that works by getting absorbed into the plant and distributed throughout all parts the plant. When an insect feeds on the plant it is poisoned. Systemic insecticides are especially good for severe infestations or reoccurring insect problems. There are two forms of systemic insecticides, one is a granule that gets mixed into the soil and is taken up into the plant by the roots. This form of systemic takes time to take effect, often 5-10 days. The other form is spray systemics. This form of systemic is sprayed onto the plant's leaves and is absorbed into the plant. This form works like a spray insecticide, killing insects on contact, then works as a systemic for lasting control.

*** A systemic insecticide will make any plant poisonous. Be sure to keep any and all plants treated with a systemic insecticide out of reach of children and animals. ***

The most important part of insect control is early detection. A few insects on a plant is much easier to get rid of than an infestation of hundreds on several plants. Check plants often for any sign of insect presence and if found, act quickly. Keep affected plants away from other plants to prevent the insects from spreading to other plants. Keeping plants clean by spraying plants with water about once a month will not only wash away dust and dirt but also any insects that may have found their way into your home, preventing them from evolving into an out of control infestation.

I hope this helps. If you have any questions or need additional information please don't hesitate to ask.
     Thanks
       Tracy