Lots of Peach Leaf Curl and few apricots, but not all is lost

A wet winter and spring means the peaches and nectarines have a bad case of leaf curl.


Several people have said things to me this spring to the effect that with all the rain, my fruit trees must be doing great. Well, for those that are prone to diseases in wet years, not so much.

Moreover, the apricots and apriums have set little or no fruit, with one exception. It was probably too wet and cool during their bloom; they did bloom well and are not currently showing any disease problems. Just fruitless. (The exception is the ‘Canadian White Blenheim‘ apricot, which has a lot of fruit; this variety rarely blooms well or sets more than one or two. Go figure.)

On the good side, the plums and pluots have set well.

Also on the good side is that the peaches and nectarines have better fruit set than usual. The leaf curl should not affect the fruit. The biggest problem is that the infected leaves will dry and fall off in coming weeks. The trees will replace them, but of course, this means the trees will be stressed and have less energy for fruit than if they had avoided the disease. But they should come through OK, at least if my past experience is any guide. This is, however, the worst peach leaf curl outbreak I can recall ever seeing in any of my orchards.

The many spring phases of the Bartlett pear

The old ‘Bartlett’ pear–it was already well established when we arrived at this location four years ago–displays both good and bad signs of spring.


At the bottom of the image we see flowers open and also a bud not yet open, as well as (at the very bottom) little fruitlets that appear to have set, post-bloom. There is lots of lush-looking new foliar growth.

At the same time, we see leaves that are blackened and wilted. These are the early signs of Fire Blight, a serious disease pest of pear trees. Bartlett is one of the worst-affected varieties. Notice also lots of deadwood; these are branches and twigs that were killed by Fire Blight last year or longer ago (and which I’ve not gotten around to pruning out because the tree’s upper parts are somewhat difficult to reach).

Fire Blight may eventually kill this tree. In the meantime, it is capable of fruiting, and we have had delicious fruit from this tree in recent years. This year looked promising, as there was a good bloom and growth surge, despite how awful it looked due to the blight at the end of last summer. However, it seems little of this spring’s fruit set has held.

I had to expect this to be a bad year for Fire Blight–well, a good year from the perspective of the blight–because it was so wet. Many fruit tree diseases really thrive after an unusually rainy winter and spring. And no year on record in California has been as unusually rainy as this one has been.

The photo was taken on 12 April. Two weeks later, the blight has only spread, although the tree continues to put out new foliar growth. It is a survivor, and will push on at least a while longer.

UK 2017: Green Party won’t stand in Ealing constituency

Here is something we do not see in First-Past-the-Post elections* as much as the Duvergerianists seem to think we should: one party agreeing not to have a candidate in order to avoid vote-splitting in a district.

The Green Party has pulled out of a crucial election seat in a bid to help the Labour Party beat the Tories – the first tactical withdrawal of its kind ahead of the general election.

The decision is expected to allow more votes to go to Labour MP Rupa Huq, who beat the Conservatives with a majority of just 274 votes in 2015, when no other party managed to attract more than seven per cent of the vote.

Green Party members in Ealing — where the party won 1,841 votes in the 2015 election — voted not to field a candidate last week, after Ms Huq promised to campaign for voting reform and the environment.

* Except in India!

BC 2017: Non-Duvergerian watch

British Columbia votes for its provincial assembly on 9 May. Eric Grenier’s vote and seat projections at CBC suggest it could be a “non-Duvergerian” outcome, especially in the votes. The NDP looks likely to win a majority of seats, manufactured by the electoral system, as its votes are likeliest to stay below 45%. The Liberals are running well behind, but are also likely to be over-represented due to their more efficient votes distribution: Grenier’s average projection for the party would put them on just under 35% of votes but 39% of seats.

The non-Duvergerian aspect of the election is the Greens: average projection of 20% of the votes, which is on the high side for a third party under FPTP. The mechanical effect will crush them, however: average seats only 2 of 87. That, of course, is “typical” FPTP.

Where things get interesting is if the Greens rise even just a few percentage points. The “high” projection takes their votes up only to around 23% but their seats to 12 or more (around 14%)! Clearly, they are running second in many districts–particularly on Vancouver Island.

The reason this pattern is non-Duvergerian is that the so-called Duverger’s law says voters tend not to want to waste their votes on a third party. They should “coordinate” with the more-preferred of the two big parties. Further, this defection should be more likely after the third party has suffered from the mechanical effect of FPTP in past elections, as the Greens in BC have. Instead, their support is evidently growing.

But there is not much incentive to choose between the major parties when you have three-party competition throughout much of the province, and the third party could win a significant number of seats even if it stays well below 50% in the districts where it is most viable.

The BC NDP platform promises: “We’ll hold a referendum – and campaign for the “yes” side – on replacing our outdated voting system with a proportional one.”

Will they follow through if FPTP delivers them a majority?

Update: The tracker of where the party leaders are campaigning is interesting. Of course, there is much emphasis on swing districts, particularly for the NDP. However, this quotation from Richard Johnston (UBC political scientist) is spot on:
“You do have to campaign everywhere; you have to validate the existence of your candidates.” In Chapter 10 of Votes from Seats (forthcoming, Cambridge University Press), Rein Taagepera and I refer to this phenomenon as the “embeddedness” of districts in nationwide (here, provincewide) politics. We do not consider non-Duvergerian districts to be quite the puzzle that others do, because we expect voters to be more oriented towards the aggregate outcome than towards their own district, and parties to care about “showing the flag” even in districts they may not be very likely to win.

France: what to expect for the assembly?

I am going to assume the polls are right and Emmanuel Macron will squeak past Marine Le Pen and be elected president in the runoff in France’s presidential election. (The polls actually suggest he will win at least 60% of the vote.) Let’s think ahead to the assembly elections, which come in June (also in two rounds).

I have seen various references to a likelihood of “cohabitation”. This is nonsense, if we define that term properly to mean cases in which the president and premier are from opposing parties and the president’s party is not in the cabinet. But let’s give people saying this the benefit of the doubt, and assume they mean the presumptive President Macron will have a difficult coalition-building task ahead of him with the assembly he will face. This is not unreasonable to assume, given that Macron has no existing party to start with.

Even this weaker prediction of a challenging assembly environment for the young “outsider” president is probably wrong. Honeymoon elections really matter, and France has had, since 2002, an extreme version of a honeymoon cycle, with the assembly election only about a month after the presidential.

This first graph is from the forthcoming Votes from Seats by Rein Taagepera and Matthew Shugart (yes, me). Unlike most graphs in this book, this is not a logical model. That is, it is not based on deductive logic for the specific equation plotted. The equation is an empirical regression result. However, the basic idea of a honeymoon surge is itself well documented (as explained in Chapter 12 of the book, citing earlier work by me and others).

The plot is of the “presidential vote ratio” against “elapsed time”. The presidential vote ratio, or Rp, is the vote share of the president’s party in the assembly election, divided by the president’s own votes (in the first round, if two-round system). Elapsed time is the number of months into the presidential inter-electoral period in which the assembly election took place, so 0 means a concurrent election (same day) and the more closely elapsed time approaches 1.0, the closer it is to the next presidential election (but before it).

The upcoming French assembly election will be about 1/60=0.0167 on elapsed time, E. Macron has won, according to initial results, about 24% of the first-round vote for president. So, doing the math in the (empirical) equation, we get:


In other words, if the pattern holds for France, 2017, we should expect Macron’s new party, En Marche!, to get around 29% of the vote (24*1.19=28.6). Is that even possible, given En Marche! did not even exist prior to Macron’s campaign? I do not know, and I will not call this a “prediction” given it is just an empirical pattern and not a logical model. But there you have it, for what it is worth–in the absence of any other information, I am going with around 29% of the vote.

Note that there is only one non-concurrent election with ERp>1. Even with an untested party, I like Macron’s party’s chances of getting over 25% of the vote.

For comparison purposes, note that a largest vote-earning party in this range would not be unprecedentedly low for France. In 2012, the Socialist Party of just-elected Francois Hollande won 29.4%, and this was the largest percentage for any party in the election by a margin of 2.3 percentage points. Hollande himself had won 28.6%, so his party had only a small honeymoon boost. In 2007, Nicolas Sarkozy’s UMP did better, at 39.5%. Sarkozy himself had won 31.2%, yielding a boost about in line with that implied by the Rp equation.

Of course, what matters more is seats. Does the French electoral system tend to boost seat shares. Yes, we might say that it does. Despite the low shares for the largest party, the use of two-round majority-plurality in single-seat districts means that the largest party can expect quite a further boost indeed.

The second graph has plots of the seat share of the largest party (s1, left panel) and the effective number of seat-winning parties (NS, right panel) since 1958. The “expected” line is based on the Seat Product Model predictions. As explained in Votes from Seats (and also in Taagepera’s 2007 Predicting Party Sizes), these are based on logical models (deductive quantitative reasoning). They are not merely empirical regressions, but regression confirm them on a large dataset of national elections. They are:

s1=(MS)-.125 and NS=(MS)1/6.

MS=mean district magnitude times the assembly size

It might be noted that the previous honeymoon elections depicted here are 1981, 1988, 2002, 2007, and 2012. All show s1 above and NS below the expectation. In other words a less fragmented party system due to the honeymoon boost for the just-elected (or, in 1988, reelected) president.

Even in 2012, with his party on only 29.4% of the votes, Hollande almost had a co-partisan majority. His Socialists had 48.5% of the seats, thanks to the electoral system; with allies, he had a large working majority of over 57%.

The models assume a “simple” system–one with a single tier of allocation in one round using a basic PR formula. FPTP counts (any PR formula when M=1 is the same as plurality), but obviously majority-plurality does not, because it is not a one-round system. Even so, the worst we can say is that in some elections we get an actual seat-winning party that is bigger than predicted (for a simple system of the same number of single-seat districts) and an effective number of seat-wing parties that is lower than expected. The major exceptions to this generalization are from the 1970s. (Note the abrupt change in expected value in 1986; this was the one PR election of the Fifth Republic.)

Of course, the reason why we might expect s1 to be higher than predicted and NS to be lower is the the largest party benefits from alliance deals in the districts between rounds. But the expectation on seats–based, again, on the incorrect assumption that this is a plurality system–is not too far off, despite the fact that the votes are so fragmented that a party with just 30% in the first round is sometimes the biggest party.

We can assume that Macron and En Marche! will benefit from alliances against the National Front. It is harder to predict what the patterns will be with respect to the traditional right and left.

The bottom line is that I would expect En Marche! to emerge as the biggest party, based on the honeymoon cycle, with somewhere between 24% and 30% (maybe more!) of the vote, and somewhere between 40% and over 50% of the seats. I would further expect Macron to have no difficulty appointing a premier of his choice, and to have a ruling coalition that will be dependent on him for its very existence. Of course, I can’t say how effective this coalition will be at governing, or whether it will last Macron’s term, or even if my expectations will be proven totally wrong. But at the very least, let’s not wring our hands over prospects of a president hobbled from the start.

The electoral cycle (honeymoon elections) and the electoral system (majority-plurality) work very much in the incoming president’s favor, and these patterns may well hold even for a president from a new and untested party.

Shasta, 2015 and 2017

First photo is from March 20, 2015. Second is from April 20, 2017, from roughly the same spot. Note how the snowpack on Mt. Shasta is obviously deeper and the snow level is lower, even though the 2017 photo is from a full month later in the year.

Mt Shasta, from Hatchery Ln, near Old Stage Rd.