A dictionary of Proverbs (Oxford Paperback Reference)

walnut see a WOMAN, a dog, and a walnut tree, the more you beat them the better they be.
WALNUTS and pears you plant for your heirs
The idea of ‘planting trees for posterity’ is much older than the specific references to walnuts and pears. Cf. CICERO Cato Major vii. 24 ‘serit arbores, quae alteri saeclo prosint,’ ut ait Statius noster in Synephebis,’he plants trees, which will be of use to another age,’ as [Caecilius] Statius says in his Synephebi.

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  1640 G. HERBERT Outlandish Proverbs no. 198 The tree that growes slowly, keepes it selfe for another. 1732 T. FULLER Gnomologia no. 2401 He who plants a Walnut-Tree, expects not to eat of the Fruit. 1863 A. SMITH Dreamthorp xi. My oaks are but saplings; but what undreamed-of English kings will they not outlive?.. A man does not plant a tree for himself; he plants it for posterity. 1907 W. C. HAZLITT English Proverbs 361 Plant pears for your heirs. A proverb which no longer holds true, since pears are now made to yield well after a few years. 1941 C. MACKENZIE Red Tapeworm xv. ‘Better to plant them promptly,’ said Miss Quekett. ‘It’s only walnuts and pears you plant for your heirs.’ ■children and parents
  

If you WANT a thing done well, do it yourself
Very similar to if you would be well SERVED, serve yourself.

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  1541 M. COVERDALE tr. H. Bullinger’s Christian State of Matrimony xix. If thou wilt prospere, then loke to euery thynge thyne owne self. 1616 T. DRAXE Adages 163 If a man will haue his business well done, he must doe it himselfe. 1858 LONGFELLOW Poems (1960) 160 That’s what I always say; if you want a thing to be well done, You must do it yourself. 1927 Times 14 Nov. 15 Lastly there is the illustration of the great principle: if you want a thing done, do it yourself. 1975 ‘E. LATHEN’ By Hook or by Crook xxi. Do you know how I got it done in the end? I went down to Annapolis myself. I always say, if you want a thing done well, do it yourself! 1998 Times 20 Jan. 7 After everything that’s happened, pregnancy was the last thing on my mind. .. there’s a lot to be said for the old adage that if you want a job doing properly, do it yourself. "efficiency and inefficiency; self-help