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PIANT BUGS IIAKE STRAWBERRY "NUBBINS" 



Certain insects do cause "nubbins" in strawberries. The extent to which 

 insects and their allies are involved may vary greatly from year to year and 

 from planting to planting; there may be great variation in the different parts 

 of a single small planting depending upon the vegetation in adjacent areas. 



Some people call "nubbins" the small, undersized berries produced on weak 

 plants. Certainly these small and often off- flavored fruits are undesirable. 

 But as I am using the term "nubbins^" I am thinking of berries which may be 

 partly normal, but are otherwise hard, green, and misshapen. 



Small, but otherwise well-shaped fruits result from a number of causes, some 

 due to insect or mite activities. Severe infestations of Tvro-spotted Mite and 

 Cyclamen Mite which destroy the natural green color of the foliage and weaken the 

 plants often result in these small, almost worthless fruits. Injury by insects 

 v;hich bore into crovms or vfhich feed upon the roots of the plants may not be sev- 

 ere enough to kill the plant outright, but yet cause a weakened condition which 

 makes it impossible for the plant to produce a normal crop. 



True "nubbins", however, are very likely the result of feeding by one of the 

 sucking plant bugs. The False Tarnished Plant Bug in particular, is responsible 

 for much of this kind of abnormal fruit, Spittlebugs, the true Tarnished Plant 

 Bug and certain Stink Bugs also contribute to these losses. 



The Plant Bugs are small, brovm, rather inconspicuous insects about 1/6 to 

 i/8 of an inch long, winged and likely to be found in the more inconspicuous 

 places around a plant. They insert their beaks and suck juices from whatever 

 part of the plant they happen to be feeding upon. Their activities are not re- 

 stricted to one or even a fevj- kinds of plants, but include almost all of the com- 

 mon garden vegetables and fruits as well as most weeds and even shrubs and trees, 

 Vherever a plant part is particularly succulent, there you find a favorable loca- 

 tion for feeding by the False Tarnished Plant Bug and its relatives. 



Plant Bugs overiTinter in the adult stage in protected places in and around 

 open fields, orchards, gardens of plantings of small fruits. If brushland, 

 hedgerows or particularly vieedy patches are adjacent to stravirberry plantings, 

 these offer favorite places for the insects to hibernate successfully. With the 

 coming of vjarm weather during May and early June, the hibeniating bugs become 

 active and attack whatever plants are present and in a stage favorable for their 

 feeding. The tender tips of developing strawberry fruits offer just such a situa- 

 tion. 



As plant Bugs feed, they appear to secrete some material which causes the 

 affected plant parts to grow abnormally. Often, parts of the tissue are killed 

 outright by the action of the toxin. Strawberry fruits develop into misshapen, 

 unsalable forms which we call "nubbins". 



It should be remembered that "nubbins" caused by Plant Bugs are most likely 

 to occur in plantings or parts of plantings which are adjacent to favorable over- 

 wintering places. Rank growth of vfeeds and other vegetation located near straw- 

 berry plantings are likely to attract large numbers of Plant Bugs during the 



